On my iPad and iPhone I am getting errors that it can't get the Yahoo! mail to go through, it won't verify the data.

I can't get mai on the iPad or iphone (and maybe the macbook pro) from Yahoo!. It won't verify the info and has me to authenticate using safari. I hav a PLUS account, have deleted and restarted a new account, but no verif. It used to work, but has quit. Especially worse since running iOS 5. Apple is scheduled for expresslane for 4 - 5 days out. I don't have a current phone number for Yahoo! or I'd be bugging them. It just won't verify even after changing passwords. GMail and iCloud work fin. Any ideas ?