Upload problem

I've recently installed Omeka, so am a newbie and maybe am missing something obvious. When endeavouring to upload an text or an image via the Contribution plugin I get the following error message:

Warning: escapeshellarg() has been disabled for security reasons in /var/www/vhosts/mylifeismymuseum.eu/httpdocs/mlimm/application/models/File.php on line 16

Is this something I can fix by modifying the PHP code? or do I need to request my hosting provider to enable escapeshellarg() ?

Thanks in anticipation.

You'll have to check with your hosting service on this one.