Why not make the TimerId the chat window handle in your AddTimer call?
code:
MsgPlus.AddTimer(oChatWnd.Handle,5000);
Then in your timer event you could just enumerate the opened chat windows to find the one which has a handle that matches the TimerID:
code:
function OnEvent_Timer(sTimerId){
var e = new Enumerator(Messenger.CurrentChats);
for(; !e.atEnd(); e.moveNext()){
var ChatWindow = e.item();
if (ChatWindow.Handle == sTimerId){
//Do whatever here
}
}
}
Something like that should work...