The script whose uid is 540 is not allowed to access /tmp/phppbUM8M owned by uid 0

The problem I am struggling with is PHP and MySQL related. I have a webserver with multiple users on it and I run a PHP script to add banners to a MySQL database. This works fine, I can add both text and banners (.gif images). When I upload these PHP scripts using the username of one of the other users on my system and try to add textual data to the database I have no problem (shouldn't expect one either), but when I try to upload a banner (BLOB) I get this error message:
Warning: SAFE MODE Restriction in effect. The script whose uid is 540 is not allowed to access /tmp/phppbUM8M owned by uid 0 in /opt/guide/www.modelspoor.nl/HTML/advertenties/banneradd.php3 on line 43

In other words this script is not allowed to write and read in the /tmp dir, which does make sense, just it makes it impossible to put blobs into the database because that requires this step. How can I fix this problem in a safe way?

Thanks a lot!

[This message has been edited by bombear (edited April 28, 2000).]

Is 'safe mode' turned on in your php3.ini file? Just a guess, since your error says "SAFE MODE Restriction"...