Can't Change Permalinks

Well this is puzzling. I have a site using GeoCraft and, for my blog side of things, we want the category in the URL, but every time we change the Permalink settings in WP settings, it reverts back to PostName only.

Is there something in the theme doing this or can anyone make any suggestion? Never had this problem with WP before.

Thanks.
Martin

 

OK so I found the culprit, it's written into the theme:

Code:

function cc_reset_permalinks() {
    global $wp_rewrite;
    $wp_rewrite->set_permalink_structure('/%postname%/');
    $wp_rewrite->flush_rules();
}

So, how do I work around it? I don't want my blog post URLs to lack the category name.

Martin