Could not generate a temporary file

[Cube]

I also have this problem:

Quote:Warning: ftp_rawlist() [function.ftp-rawlist]: open_basedir restriction in effect. File(/tmp) is not within the allowed path(s): (/var/www/ispcp/gui/:/etc/ispcp/:/var/run/ispcp.lock:/proc/:/bin/df:/bin/mount:/var/log/rkhunter.log:/var/log/chkrootkit.log:/usr/share/php/) in /var/www/ispcp/gui/tools/filemanager/includes/browse.inc.php on line 123
[...]

When I add /tmp to php.ini it works again. But the reason for this error has to be somewhere else, because normally /tmp isn't in php.ini and it works (e.g. in BeNe's demo).
I use Debian Etch and the latest trunk.
Any ideas?