Error message: open_basedir restriction in effect

Hi,

I'm getting the following error message on a new installation of CMSB when I try to change a section record:

Warning: is_dir(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/usr/share/pear/:/usr/share/php/:/usr/local/pem/vhosts/115545/) in /usr/local/pem/vhosts/115545/webspace/httpdocs/ennisoft-webdev.com/cmsAdmin/lib/common.php on line 175

It happens when I add an upload field into a section editor - I remove the upload, the message stops appearing.

I also get a message telling me that the uploads folder does not exist - I have checked the paths in Server Settings, and they seem right to me.

I contacted my hosting company and they gave me the following response:

Open_basedir is no longer applicable since the PHP 5.3.3 upgrade that was made to the control panel awhile back. 
You would need to look in to the software you are using for alternatives to open_basedir where applicable, or migrate to cloud as they will require PHP 5.2

I see there are similar posts, but no solutions, they all seem to go to second level support. Any ideas?

Thanks,

Ross