diff --git a/telegram/handlers.go b/telegram/handlers.go
index 1ce1636..021280d 100644
--- a/telegram/handlers.go
+++ b/telegram/handlers.go
@@ -73,7 +73,7 @@ func (c *Client) sendMarker(chatId, messageId int64, typ gateway.MarkerType) {
 
 	gateway.SendMessageMarker(
 		c.jid,
-		strconv.FormatInt(chatId, 10),
+		gateway.CHATNODE(chatId),
 		c.xmpp,
 		typ,
 		xmppId,
@@ -390,6 +390,12 @@ func (c *Client) updateDeleteMessages(update *client.UpdateDeleteMessages) {
 			}
 		}
 
+		var isGroupchat bool
+		chat, _, _ := c.GetContactByID(update.ChatId, nil)
+		if c.Session.MUC && c.IsGroup(chat) {
+			isGroupchat = true
+		}
+
 		var deleteChar string
 		if c.Session.AsciiArrows {
 			deleteChar = "X "
@@ -397,7 +403,13 @@ func (c *Client) updateDeleteMessages(update *client.UpdateDeleteMessages) {
 			deleteChar = "✗ "
 		}
 		text := deleteChar + strings.Join(int64SliceToStringSlice(update.MessageIds), ",")
-		gateway.SendTextMessage(c.jid, strconv.FormatInt(update.ChatId, 10), text, c.xmpp)
+		var fromJid string
+		if isGroupchat {
+			fromJid = gateway.MUCJID(update.ChatId)
+		} else {
+			fromJid = gateway.CHATNODE(update.ChatId)
+		}
+		gateway.SendTextMessage(c.jid, fromJid, text, c.xmpp, isGroupchat)
 	}
 }
 
@@ -443,7 +455,7 @@ func (c *Client) updateChatTitle(update *client.UpdateChatTitle) {
 		return
 	}
 
-	gateway.SetNickname(c.jid, strconv.FormatInt(update.ChatId, 10), update.Title, c.xmpp)
+	gateway.SetNickname(c.jid, gateway.CHATNODE(update.ChatId), update.Title, c.xmpp)
 
 	// set also the status (for group chats only)
 	if user == nil {
diff --git a/telegram/utils.go b/telegram/utils.go
index ee3bc8b..c911001 100644
--- a/telegram/utils.go
+++ b/telegram/utils.go
@@ -459,14 +459,13 @@ func (c *Client) ProcessStatusUpdate(chatID int64, status string, show string, o
 	}
 
 	c.locks.mucCacheLock.Lock()
-	chatJid := strconv.FormatInt(chatID, 10) + "@" + gateway.Jid.Full()
+	chatJid := gateway.CHATJID(chatID, true)
 	for mucId, state := range c.mucCache {
 		member, ok := state.Members[chatID]
 		if ok {
-			sMucId := strconv.FormatInt(mucId, 10)
 			newMucArgs := append(
 				newArgs,
-				gateway.SPFrom(sMucId),
+				gateway.SPFrom(gateway.MUCNODE(mucId)),
 				gateway.SPResource(member.Nickname),
 				gateway.SPMUCAffiliation(member.Affiliation),
 				gateway.SPMUCJid(chatJid),
@@ -529,7 +528,7 @@ func (c *Client) sendMUCStatuses(chatID int64) {
 		c.mucCache[chatID] = mucState
 	}
 
-	sChatId := strconv.FormatInt(chatID, 10)
+	sChatId := gateway.MUCNODE(chatID)
 	myNickname := "me"
 	if c.me != nil {
 		myNickname = c.getFullName(c.me)
@@ -542,8 +541,6 @@ func (c *Client) sendMUCStatuses(chatID int64) {
 		Filter: &client.ChatMembersFilterMembers{},
 	})
 	if err == nil {
-		gatewayJidSuffix := "@" + gateway.Jid.Full()
-
 		for _, member := range members.Members {
 			var senderId int64
 			switch member.MemberId.MessageSenderType() {
@@ -573,7 +570,7 @@ func (c *Client) sendMUCStatuses(chatID int64) {
 				gateway.SPResource(nickname),
 				gateway.SPImmed(true),
 				gateway.SPMUCAffiliation(affiliation),
-				gateway.SPMUCJid(strconv.FormatInt(senderId, 10) + gatewayJidSuffix),
+				gateway.SPMUCJid(gateway.CHATJID(senderId, true)),
 			)
 		}
 	}
@@ -592,7 +589,7 @@ func (c *Client) sendMUCSubject(chatID int64, resource string) {
 	pin, err := c.client.GetChatPinnedMessage(&client.GetChatPinnedMessageRequest{
 		ChatId: chatID,
 	})
-	mucJid := strconv.FormatInt(chatID, 10) + "@" + gateway.Jid.Bare()
+	mucJid := gateway.MUCJID(chatID)
 	toJid := c.jid + "/" + resource
 	if err == nil {
 		gateway.SendSubjectMessage(
@@ -617,7 +614,7 @@ func (c *Client) updateMUCsNickname(memberID int64, newNickname string) {
 	c.locks.mucCacheLock.Lock()
 	defer c.locks.mucCacheLock.Unlock()
 
-	realJid := strconv.FormatInt(memberID, 10) + "@" + gateway.Jid.Full()
+	realJid := gateway.CHATJID(memberID, true)
 	for mucId, state := range c.mucCache {
 		oldMember, ok := state.Members[memberID]
 		if ok {
@@ -626,7 +623,7 @@ func (c *Client) updateMUCsNickname(memberID int64, newNickname string) {
 				Affiliation: oldMember.Affiliation,
 			}
 
-			sMucId := strconv.FormatInt(mucId, 10)
+			sMucId := gateway.MUCNODE(mucId)
 			unavailableStatusCodes := []uint16{303, 210}
 			availableStatusCodes := []uint16{100, 210}
 			if c.me != nil && memberID == c.me.Id {
@@ -1445,7 +1442,7 @@ func (c *Client) SendMessageToGateway(chatId int64, message *client.Message, id
 
 		senderId := c.getMessageSenderId(message)
 		if senderId != 0 {
-			originalFrom = strconv.FormatInt(senderId, 10) + "@" + gateway.Jid.Full()
+			originalFrom = gateway.CHATJID(senderId, true)
 		}
 	}
 
@@ -1552,7 +1549,7 @@ func (c *Client) SendMessageToGateway(chatId int64, message *client.Message, id
 
 	var from string
 	if groupChatFrom == "" {
-		from = strconv.FormatInt(chatId, 10)
+		from = gateway.CHATNODE(chatId)
 	} else {
 		from = groupChatFrom
 	}
@@ -1693,11 +1690,10 @@ func (c *Client) ProcessOutgoingMessage(chatID int64, text string, returnJid str
 }
 
 func (c *Client) returnMessage(returnJid string, chatID int64, text string, code int, isGroupchat bool) {
-	sChatId := strconv.FormatInt(chatID, 10)
 	if isGroupchat {
-		gateway.SendErrorMessage(returnJid, sChatId + "@" + gateway.Jid.Bare(), text, code, isGroupchat, c.xmpp)
+		gateway.SendErrorMessage(returnJid, gateway.MUCJID(chatID), text, code, isGroupchat, c.xmpp)
 	} else {
-		gateway.SendTextMessage(returnJid, sChatId, text, c.xmpp)
+		gateway.SendTextMessage(returnJid, gateway.CHATNODE(chatID), text, c.xmpp, isGroupchat)
 	}
 }
 
@@ -2005,7 +2001,7 @@ func (c *Client) subscribeToID(id int64, chat *client.Chat) {
 
 		args = append(args, gateway.SPNickname(chat.Title))
 
-		gateway.SetNickname(c.jid, strconv.FormatInt(id, 10), chat.Title, c.xmpp)
+		gateway.SetNickname(c.jid, gateway.CHATNODE(id), chat.Title, c.xmpp)
 	}
 
 	c.sendPresence(args...)
@@ -2080,7 +2076,7 @@ func (c *Client) UpdateChatNicknames() {
 
 			c.sendPresence(newArgs...)
 
-			gateway.SetNickname(c.jid, strconv.FormatInt(id, 10), chat.Title, c.xmpp)
+			gateway.SetNickname(c.jid, gateway.CHATNODE(id), chat.Title, c.xmpp)
 		}
 	}
 }
@@ -2240,10 +2236,10 @@ func (c *Client) memberStatusToAffiliation(memberStatus client.ChatMemberStatus)
 }
 
 func (c *Client) sendMessagesReverse(chatID int64, messages []*client.Message, plain bool, toJid string) {
-	sChatId := strconv.FormatInt(chatID, 10)
+	sChatId := gateway.CHATNODE(chatID)
 	var mucJid string
 	if toJid != "" {
-		mucJid = sChatId + "@" + gateway.Jid.Bare()
+		mucJid = gateway.MUCJID(chatID)
 	}
 
 	for i := len(messages) - 1; i >= 0; i-- {
diff --git a/xmpp/gateway/gateway.go b/xmpp/gateway/gateway.go
index 990ba42..255fd76 100644
--- a/xmpp/gateway/gateway.go
+++ b/xmpp/gateway/gateway.go
@@ -61,6 +61,32 @@ var DirtySessions = false
 // MessageOutgoingPermissionVersion contains a XEP-0356 version to fake outgoing messages by foreign JIDs
 var MessageOutgoingPermissionVersion = 0
 
+// CHATNODE converts numeric id to node part of 1-1 chat JID
+func CHATNODE(chatId int64) string {
+	return strconv.FormatInt(chatId, 10)
+}
+
+// CHATJID converts numeric id to 1-1 chat JID
+func CHATJID(chatId int64, full bool) string {
+	var suffix string
+	if full {
+		suffix = Jid.Full()
+	} else {
+		suffix = Jid.Bare()
+	}
+	return CHATNODE(chatId) + "@" + suffix
+}
+
+// MUCNODE converts numeric id to node part of MUC JID
+func MUCNODE(chatId int64) string {
+	return "c" + CHATNODE(chatId)
+}
+
+// MUCJID converts numeric id to MUC JID
+func MUCJID(chatId int64) string {
+	return "c" + CHATJID(chatId, false)
+}
+
 // SendMessage creates and sends a message stanza
 func SendMessage(to, from, body, id string, component *xmpp.Component, reply *Reply, timestamp int64, replaceId string, isCarbon, isGroupchat, requestReceipt bool, originalFrom string) {
 	sendMessageWrapper(to, from, body, "", "", id, component, reply, nil, timestamp, "", replaceId, isCarbon, isGroupchat, false, requestReceipt, originalFrom, 0, "")
@@ -76,12 +102,12 @@ func SendServiceMessage(to, body string, component *xmpp.Component) {
 }
 
 // SendTextMessage creates and sends a simple message stanza
-func SendTextMessage(to, from, body string, component *xmpp.Component) {
+func SendTextMessage(to, from, body string, component *xmpp.Component, isGroupchat bool) {
 	var id string
 	if uuid, err := uuid.NewRandom(); err == nil {
 		id = uuid.String()
 	}
-	sendMessageWrapper(to, from, body, "", "", id, component, nil, nil, 0, "", "", false, false, false, false, "", 0, "")
+	sendMessageWrapper(to, from, body, "", "", id, component, nil, nil, 0, "", "", false, isGroupchat, false, false, "", 0, "")
 }
 
 // SendErrorMessage creates and sends an error message stanza
@@ -536,7 +562,7 @@ func SendPresence(component *xmpp.Component, to string, args ...args.V) error {
 
 // SPAppendFrom appends numeric from and resource to varargs
 func SPAppendFrom(oldArgs []args.V, id int64) []args.V {
-	newArgs := append(oldArgs, SPFrom(strconv.FormatInt(id, 10)))
+	newArgs := append(oldArgs, SPFrom(CHATNODE(id)))
 	newArgs = append(newArgs, SPResource(Jid.Resource))
 	return newArgs
 }
@@ -626,7 +652,7 @@ func SendPubSubAvatarNotification(component *xmpp.Component, jid string, chatId
 
 	message := stanza.Message{
 		Attrs: stanza.Attrs{
-			From: strconv.FormatInt(chatId, 10) + "@" + Jid.Bare(),
+			From: CHATJID(chatId, false),
 			To:   jid,
 			Type: stanza.MessageTypeHeadline,
 		},
@@ -637,6 +663,5 @@ func SendPubSubAvatarNotification(component *xmpp.Component, jid string, chatId
 }
 
 func InviteToMUC(chatID int64, jid string, component *xmpp.Component) {
-	sChatID := strconv.FormatInt(chatID, 10)
-	SendMUCInvite(jid, sChatID, component, Jid.Full())
+	SendMUCInvite(jid, MUCNODE(chatID), component, Jid.Full())
 }
diff --git a/xmpp/handlers.go b/xmpp/handlers.go
index 2f3cb0a..506d9e6 100644
--- a/xmpp/handlers.go
+++ b/xmpp/handlers.go
@@ -128,7 +128,7 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 			return
 		}
 
-		toID, ok := toToID(msg.To)
+		toID, ok, toIsGroup := toToID(msg.To)
 		if ok {
 			toJid, err := stanza.NewJid(msg.To)
 			if err != nil {
@@ -138,15 +138,22 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 
 			isGroupchat := msg.Type == "groupchat"
 
-			if session.Session.MUC && toJid.Resource != "" {
+			if session.Session.MUC {
 				chat, _, err := session.GetContactByID(toID, nil)
 				if err == nil && session.IsGroup(chat) {
-					if isGroupchat {
-						gateway.SendErrorMessageWithBody(msg.From, msg.To, msg.Body, "", msg.Id, 400, true, component)
-					} else {
-						gateway.SendErrorMessage(msg.From, msg.To, "PMing room members is not supported, use the real JID", 406, true, component)
+					if !toIsGroup {
+						gateway.SendErrorMessage(msg.From, toJid.Node, "KHVATIT SYUDA ZVONITb", 403, false, component)
+						return
+					}
+
+					if toJid.Resource != "" {
+						if isGroupchat {
+							gateway.SendErrorMessageWithBody(msg.From, msg.To, msg.Body, "", msg.Id, 400, true, component)
+						} else {
+							gateway.SendErrorMessage(msg.From, msg.To, "PMing room members is not supported, use the real JID", 406, true, component)
+						}
+						return
 					}
-					return
 				}
 			}
 
@@ -210,13 +217,21 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 				chatId, msgId, err := gateway.IdsDB.GetByXmppId(session.Session.Login, bare, replace.Id)
 				if err == nil {
 					if chatId != toID {
-						gateway.SendTextMessage(msg.From, strconv.FormatInt(toID, 10), "<ERROR: Chat mismatch>", component)
+						if isGroupchat {
+							gateway.SendErrorMessage(msg.From, gateway.MUCJID(toID), text, 400, isGroupchat, component)
+						} else {
+							gateway.SendTextMessage(msg.From, gateway.CHATNODE(toID), "<ERROR: Chat mismatch>", component, isGroupchat)
+						}
 						return
 					}
 					replaceId = msgId
 					log.Debugf("replace tg: %#v %#v", chatId, msgId)
 				} else {
-					gateway.SendTextMessage(msg.From, strconv.FormatInt(toID, 10), "<ERROR: Could not find matching message to edit>", component)
+					if isGroupchat {
+						gateway.SendErrorMessage(msg.From, gateway.MUCJID(toID), text, 400, isGroupchat, component)
+					} else {
+						gateway.SendTextMessage(msg.From, gateway.CHATNODE(toID), "<ERROR: Could not find matching message to edit>", component, isGroupchat)
+					}
 					return
 				}
 			}
@@ -313,7 +328,7 @@ func HandleMessage(s xmpp.Sender, p stanza.Packet) {
 			if !ok {
 				return
 			}
-			toID, ok := toToID(msg.To)
+			toID, ok, _ := toToID(msg.To)
 			if !ok {
 				return
 			}
@@ -385,7 +400,7 @@ func handleSubscription(s xmpp.Sender, p stanza.Presence) {
 
 	_ = gateway.ResumableSend(component, reply)
 
-	toID, ok := toToID(p.To)
+	toID, ok, _ := toToID(p.To)
 	if !ok {
 		return
 	}
@@ -502,8 +517,8 @@ func handleMUCPresence(s xmpp.Sender, p stanza.Presence, mucExt stanza.MucPresen
 				return
 			}
 
-			chatId, ok := toToID(toBare)
-			if !ok {
+			chatId, ok, toIsGroup := toToID(toBare)
+			if !ok || !toIsGroup {
 				presenceReplySetError(reply, 404)
 				return
 			}
@@ -562,8 +577,8 @@ func tryHandleMUCNicknameChange(s xmpp.Sender, p stanza.Presence) {
 		return
 	}
 
-	chatId, ok := toToID(toBare)
-	if !ok {
+	chatId, ok, toIsGroup := toToID(toBare)
+	if !ok || !toIsGroup {
 		return
 	}
 
@@ -663,7 +678,7 @@ func handleGetAvatarDataIq(s xmpp.Sender, iq *stanza.IQ, pubsub *stanza.PubSubGe
 		return
 	}
 
-	chatId, ok := toToID(iq.To)
+	chatId, ok, _ := toToID(iq.To)
 	if !ok {
 		log.Errorf("Invalid chat id in To JID %v", iq.To)
 		return
@@ -764,7 +779,7 @@ func handleGetAvatarDataIq(s xmpp.Sender, iq *stanza.IQ, pubsub *stanza.PubSubGe
 }
 
 func getTelegramChatType(from string, to string) (telegram.ChatType, error) {
-	toId, ok := toToID(to)
+	toId, ok, _ := toToID(to)
 	if ok {
 		bare, _, ok := gateway.SplitJID(from)
 		if ok {
@@ -809,14 +824,14 @@ func handleGetDiscoInfo(s xmpp.Sender, iq *stanza.IQ, di *stanza.DiscoInfo) {
 	defer gateway.ResumableSend(component, answer)
 
 	disco := answer.DiscoInfo()
-	toID, toOk := toToID(iq.To)
+	toID, toOk, toIsGroup := toToID(iq.To)
 
 	if di.Node == "" {
 		var isMuc bool
 		bare, _, fromOk := gateway.SplitJID(iq.From)
 		if fromOk {
 			session, sessionOk := sessions[bare]
-			if sessionOk && session.Session.MUC {
+			if sessionOk && session.Session.MUC && toIsGroup {
 				if toOk {
 					chat, _, err := session.GetContactByID(toID, nil)
 					if err == nil && session.IsGroup(chat) {
@@ -907,7 +922,7 @@ func handleGetDiscoItems(s xmpp.Sender, iq *stanza.IQ, di *stanza.DiscoItems) {
 
 	log.Debugf("discoItems: %#v", di)
 
-	toID, toOk := toToID(iq.To)
+	toID, toOk, _ := toToID(iq.To)
 
 	disco := answer.DiscoItems()
 
@@ -959,10 +974,9 @@ func handleGetDiscoItems(s xmpp.Sender, iq *stanza.IQ, di *stanza.DiscoItems) {
 				// raw access, no need to create a new instance if not connected
 				session, sessionOk := sessions[bare]
 				if sessionOk && session.Session.MUC {
-					bareJid := gateway.Jid.Bare()
-					disco.AddItem(bareJid, "", "Telegram group chats")
+					disco.AddItem(gateway.Jid.Bare(), "", "Telegram group chats")
 					for _, chat := range session.GetGroupChats() {
-						jid := strconv.FormatInt(chat.Id, 10) + "@" + bareJid
+						jid := gateway.MUCJID(chat.Id)
 						disco.AddItem(jid, "", chat.Title)
 					}
 				}
@@ -1085,7 +1099,7 @@ func handleSetQueryCommand(s xmpp.Sender, iq *stanza.IQ, command *stanza.Command
 	if !ok {
 		return
 	}
-	toId, toOk := toToID(iq.To)
+	toId, toOk, _ := toToID(iq.To)
 
 	var cmdString string
 	var cmdType telegram.CommandType
@@ -1603,19 +1617,25 @@ func sendPubSubAvatarNotifications(s xmpp.Sender, jid string, session *telegram.
 	}
 }
 
-func toToID(to string) (int64, bool) {
+func toToID(to string) (int64, bool, bool) {
+	var isGroup bool
 	toParts := strings.Split(to, "@")
 	if len(toParts) < 2 {
-		return 0, false
+		return 0, false, isGroup
 	}
-	toID, err := strconv.ParseInt(toParts[0], 10, 64)
+	node := toParts[0]
+	if strings.HasPrefix(node, "c") {
+		isGroup = true
+		node = node[1:]
+	}
+	toID, err := strconv.ParseInt(node, 10, 64)
 	if err != nil {
 		log.WithFields(log.Fields{
 			"to": to,
 		}).Error(errors.Wrap(err, "Invalid to JID!"))
-		return 0, false
+		return 0, false, isGroup
 	}
-	return toID, true
+	return toID, true, isGroup
 }
 
 func makeVCardPayload(typ byte, id string, info telegram.VCardInfo, session *telegram.Client) stanza.IQPayload {