PHP Sessions not working on one site!

[badben]

I have ispconfig running on mandrake 10.2 using perfect setup.

The problem is that on one of my sites sessions don't work and on the others they do.

On the site that they don't work zencart is installed in folder web/zencart/ and sessions are set to be stored in a database.

Does anybody know if this will change where sessions are stored for the whole site i.e a script in web/?

there are no settings in the apache directives for either site and the site settings in ispconfig are identical for both sites.

Ben