Forum Weird Behaviour when trying to enable Facebook Connect
 

So I have been trying to enable Facebook Connect on a VBulletin Forum

On Chrome I get this error message and the forum doesn't show at all:

Warning: session_start() [function.session-start]: Function spl_autoload_call() hasn't defined the class it was called for in [path]/includes/facebook/facebook.php on line 37

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at [path]/includes/class_core.php:5615) in [path]/includes/facebook/facebook.php on line 37

Warning: Cannot modify header information - headers already sent by (output started at [path]/includes/class_core.php:5615) in [path]/includes/functions.php on line 4513:


On IE I get this error message, but it shows the forum but with no FacebooK Connect Option:


Warning: session_start() [function.session-start]: Function spl_autoload_call() hasn't defined the class it was called for in [path]/includes/facebook/facebook.php on line 37

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at [path]/includes/class_core.php:5615) in [path]/includes/facebook/facebook.php on line 37

Finally on Aurora (Firefox) I don't see any error messages and the forum and Facebook Connect all seem to work.

Does anyone have any suggestions as to what might be causing this?