It’s has been more than half year since we have Yahoo connection problem in Adium for Mac users. I have tried all ways to fix this solution, but nothing works. The only forum that i can hope to find solution is Cocoaforge forum thread. I have been checking on this thread for months and the day i was waiting finally come. Many thanks to djharris in the forum for sharing the patched version of Adium to solve this problem. He applied the patch in ticket 16678 to Adium 1.5.10 source code and then built it. And to fix Yahoo connection issue, you can just download the patched Adium version i uploaded in this link.
Next thing you do, just copy Adium.app inside the zip file to your Applications folder. I have tried this by myself, and I can log in to Yahoo and can see my buddy list. It’s verified that i already succeed sending messages and have a chat with my friends using this patch.