trouble staying logged in in Firefox 3.0

trouble staying logged in in Firefox 3.0

whenever I close Firefox 3.0 I get logged out of Zoho SSO when I open it again.

Please note the following:
-I am using XP Pro
-I am not clearing cache and cookies
-This is only SSO, I am still logged into Zoho CRM
-Yes, I checked the "remember me" box
-This problem does not occur in IE7

Any feedback would be appreciated. Thanks.