AT&T has fixed several problems that caused some AT&T customers to log into the wrong Facebook account when using their mobile phones, an AT&T spokesman said on Monday: "In a limited number of instances, a server software connectivity error resulted in some AT&T wireless customers being logged in to the wrong Facebook account when they accessed Facebook through their mobile phones."

AT&T added new security measures to prevent the problem from happening again and worked with Facebook to disable subscriber identification information as an option for automatic log-on, Coe said. The subscriber identification is the session identification number that gets added to the URL, he said.

AT&T also fixed a separate problem in which a customer in Atlanta was able to log into the wrong Facebook account on a mobile phone. In that "isolated" case, the problem was due to a misdirected cookie on the customer's phone, Coe said.

"We worked with the customer to resolve the issue," he said. "It is unclear how this cookie was set on the phone."

Asked for comment, a Facebook spokesman said: "We don't have anything more than what AT&T is saying."

The Associated press first reported on the problems this weekend.

AT&T Fixes Mobile Facebook ProblemsThis story originally appeared on CNET