Using multiple Gtalk at the same time....

1. Select the Gtalk.exe file.

2. Right click and select Properties > Shortcut.

3. In the Target section Paste ""C:\Program Files\Google\Google Talk\googletalk.exe" /nomutex"

4. Don't forget to add /nomutex at the end.

If this doesn't work:

1. Copy the Gtalk.exe file from the C:\Program File\Google\GTalk and paste it on the desktop.

2. Follow all the above steps.

Hope this helps you... If not revert back...

Enjoy!!!!