[TYPO3-english] User timeout delay

[Simon]

I have only recently installed version 4.5.0 but I notice a problem with the timeout options.  A message box appears stating that the user is about to be logged out and provided two buttons one to select 
to stay logged in and the other to log out.

I have clicked the "stay logged in" button however this just appears to cycle with the dialog box reappearing - the only way I have found to get out of this cycle is to log out.

I am using Firefox 3.6.13

Thanks.

Simon