Here is a nice workaround that lets you login to the GoogleTalk clent via Pidgin. Right Click on your Google Account in Pidgin and click on modify. Then select the Advanced tab. In the dialog box that opens, Check the "Force Old (port 5223) SSL" option.
Set the connect port as 443 and the connect server as talk.google.com. And Select Proxy Type as No Proxy from the DropDown menu list.
Check the image below for the settings snapshot: