Fatal Error with sessions.php

[prazim]

Can you advise what i might do to resolve this error?:

 

Fatal error: Cannot redeclare _sess_open() (previously declared in */catalog/includes/functions/sessions.php:23) in */catalog/includes/functions/sessions.php on line 23

 

I occurs right after I log into my account as a user of the shopping cart.

 

Thanks,

Sue