image / bbcode url in subdomain

[skulls]

The goods:

SMF 2.0.2
Coppermine 1.5.20


The (sub)domain:

both reside within the same subdomain.  Let's say it's foo.forum.com  The gallery is within foo.forum.com/gallery

However, when viewing an image the Image URL reads "http://www.forum.com/gallery/userpics/......" instead of "http://foo.forum.com/gallery/userpics/...."

The Coppermine URL is set right within General Settings.  How can I change the www to foo?  Thanks!! 

[Αndré]

Please post a link to your gallery.