Moved hosts, now getting error "Error: Could not open lock file"

I have reinstalled gallery on a new host, and copied across my \albums directory. Unfortunately, I didn't get the .users directory with it (now lost to my old host).

I can now see the gallery, but get the following error all the time:

Warning: fopen(/customersites/7/home/httpd/vhosts/camdens.net/httpdocs/portfolio/albums/waterscapes/photos.dat.lock): failed to open stream: Permission denied in /customersites/7/home/httpd/vhosts/camdens.net/httpdocs/portfolio/platform/fs_unix.php on line 58
Error: Could not open lock file (/customersites/7/home/httpd/vhosts/camdens.net/httpdocs/portfolio/albums/waterscapes/photos.dat.lock) for writing!

If I refresh the page, the error goes away.
I figure it's a permissions issue (duh!).

Most of the files on my server are owned by me, but the relevent ones above are owned by "apache". Is there anyway I can take ownership of the files in order to change permissions, or does that depend on the host? At the moment I don't have permissions to CHMOD.

Thanks in advance.

Neil

The following information is required to get an answer:
Get this information from the PHP diagnostic (in the configuration wizard).
Gallery URL (optional but very useful): http://www.camdenphotography.co.uk
Gallery version:1.5.1
Apache version:1.3.29
PHP version (don't just say PHP 4, please):4.4.2
Graphics Toolkit:
Operating system:
Web browser/version (if applicable):