"Warning: session_start(): open(/tmp/" error

Same server as my old gallery (works fine), but different virtual server (basically making a version 2 of my site).

Have searched the forum for about an hour but the search facility returns nothing close even when I search for the above subject line.

The gallery seems to work fine, but I get this error:
Warning: session_start(): open(/tmp/sess_f68564c71ac19b71467776f51048efc9, O_RDWR) failed: Permission denied (13) in /home/n/e/nemesistwo/public_html/photos/session.php on line 60

I have been through the config again and set all the paths etc. I have also chmod my tmp directory to 777.

Any Ideas? I know it's it's just a simple mistake on my part as the version one of the site works fine on the same server.

Aaryn

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Get this information from the PHP diagnostic (in the configuration wizard).
Gallery URL (optional but very useful):
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PHP version (don't just say PHP 4, please):
Graphics Toolkit:
Operating system:
Web browser/version (if applicable):