Help needed: is_dir() [function.is-dir]: open_basedir restriction in effect.

Hello,
I am still new-ish to Drupal.

I recently moved my site from local machine to a test online site. When I try to create content, I get this:

warning: is_dir() [function.is-dir]: open_basedir restriction in effect. File(/Applications/MAMP/tmp/php) is not within the allowed path(s): (/var/www/vhosts/ermep.com/subdomains/test/httpdocs:/tmp) in /var/www/vhosts/ermep.com/subdomains/test/httpdocs/includes/file.inc on line 102.

I created the directory /var/www/vhosts/ermep.com/subdomains/test/httpdocs:/tmp/php and understand that I need to replace the old /Applications/MAMP/tmp/php with this new one. I tried to do that in the file systems (admin/settings/file-system) but it tells me The directory /var/www/vhosts/ermep.com/subdomains/test/httpdocs:/tmp/php does not exist. I cleared the cache, I opened the file.inc file and went to line 102, but it does not seem to be there either...

Can anybody help?

Thanks,

Sebastien.