Carefully follow the instruction…
1. Right click on desktop
2. Select New
3. Select Shortcut
4. Pastethis into the text box (including qoutes , assuming your programm files are in C drive) :
“c:program filesgooglegoogle talkgoogletalk.exe” /nomutex
5. Click Next and choose a shortcut name such as Google Talk 1, Google Talk2, or something for easy remembering which account is which.
6. Click finish and you are done.
7. If you want to login into your secondary gmail account, click on it and sign in.
( Note: You have to create a shortcut for every multiple login and use it, i.e., one shortcut can be used to login into one account only )
[Credits goes to techvi]