Yahoo! login bug

I think there is a login bug for IDs with "." in them. The 2 acounts I have made before the ne Yahoo site conversion had a "." in the emails' logins I just wanted to see if it is a bug sorry for being a pain, I worked on this and thought more about it today and realized that the 2 that do still work have no "." Go figure if that is it! Thanks for your help. I know I have no password or keyboard or other user related issues, the others still work and didn't just stop letting me log in. It's only been a problem since the recent upgrade it seems. I reported an error I got originally when I had the cookie still I thought Yahoo was down but it was because of a log in bug I'm sure of it. Even if it is or isn't how do we recover our accounts? I worked on this problem all night till I realized after accessing the 2 I can even after last night. I was positive I was hacked but I seriously doubt that is it. Please, do look into it? Thanks in advance!