php simple change for logon and logoff to different page

I currently have 2 login pages in php [login to view URL] and [login to view URL] which go to the same main page. Currently they both logoff back to the same page [login to view URL] so depending on which login page was used i want it to log off back to same login page I will provide some of the pages here, i can add the code myself, so i just need really need know how to do it etc... ## Deliverables see attchd files for more info