I just came along a problem while logging into my Google Talk account via Trillian.
Google interprets a login attempt as a security breach if it came from an application not using Google’s Single Sign On mechanism… I received an email asking me to reset my Google password. But actually a password change is not required:
You are asked if it was you who tried to access your account. If so, you need to log in w/ this very application within the next 10 minutes. Then you are all set.