It seems my Trillian at work started crashing as if it's broken, after several installs and de-installs and fooling with it I figured it out. I renamed the yahoo.ini file to old_yahoo.ini and like a miracle Trillian started to work again.
It seems after reading a recent article on CNET News.com that Yahoo! is taking all it's toys and going home.
Tired of third parties being used instead of their messenger they are now blocking every messenger including the older versions of their own. Makes no sense to anyone but Yahoo! as some folks are happy with their third party and older yahoo messenger software.
I'd suggest everyone dump Yahoo and use Jabber: Open Instant Messaging as it is a open source IM system.