Firefox login issue

I have a website that has an issue with Firefox. The site requires that users re-authenticate between each page. This issue does not occur when using IE, Chrome or Safari. The authentication is made via Active Directory using Active Directory Integration version 1.1.3. Any help on where to look or any links to information would be greatly appreciated.

A little background. I’ve been a web application developer for about 2 years, but mostly in ASP.NET. I am completely new to WordPress and I’m trying to catch up. I have taken a job where part of my duties is to develop for three sites that run WordPress. Only one of these sites has the Firefox issue. The issue was here when I started three weeks ago, so I can not give information as to when it started.