open_basedir restriction on domains running inside subfolders of other domains

[ShoneA]

I was all excited to see the feature where our clients could run a subfolder of one of their domains as a different domain. First thing I noticed when I tried to set up a second store in Magento was that our system was kicking out open_basedir restrictions, which doesn't seem right at all since everything is under that clients account, they aren't trying to access anything else but the previous directory (the main domain's root folder).

Is this intentional or do I have my Plesk configuration wrong? I know I can do manual workarounds but I had hopes I wouldn't need to do any of that.