Multi Google Talk
Just follow the simple steps Below:
1)Right click on the Google Talk shortcut.(note that this is not the one on the task bar it is the one on desktop or on START menu).
2)click on Properties.
3)Go to Shortcut tab on Google Talk Properties window.
4)On the Target textbox, add in the /nomutex to the end of the line so that it looks like below (or you can simply copy and paste the below syntax and replace the original).