There were many times reported about the way chat is working – when user1 is sending chat message to user2, user2 is getting pop-up window with Accept/Delcine chat request question.
Many people have pop-up blocker activated and in that case vldPersonals system displays Alert window saying user to turn off pop-up blocker to be able to chat.
A lot of admins think that it’s not usable (and I agree with them) because lots of their site users have not any idea about pop-up blockers and the way how to turn it off.
Trying to solve that issue first time I was thinking of jquery modal windows (similar to lightbox) but then I found easier and better way. I noticed that when user1 is clicking Chat Now! link he’s not getting any pop-up blocking situation so why don’t we try to get something similar on user2’s side?
In our case user2 will get Chat request notice link with blinking gif:
 

 
Here is step-by-step instruction for you:
 
1. Place .gif file to your DocumentRoot/media/ folder
2. Place contents of openChatWindow.txt instead of function openChatWindow of /includes/js/misc.js file
3. Place in /yourtemplatesfolder/header.tpl anywhere you want (I put it under Logout link of the user menu, right above closing ul tag) Here you are! Press couple of times F5 in your browser to apply changes!
You can modify your code to achieve all your design goals.
Download source code (developed for vldP 2.5.1, tested on FF3, IE6, Google Chrome)