So I found the following bug in the Arras Theme while going through the progress of upgrading WordPress from whatever to 3.0 and the Arras Theme from 1.3.5 to 1.4.2.
All pages started giving me this warning and unexpected behavior:
Warning: unserialize() expects parameter 1 to be string, object given in /var/www/siggis_projects/wp-content/themes/arras-theme_1.4.2/library/admin/options.php on line 86
If I take a look at what is in line 86 of options.php I see this:
$saved_options = unserialize(get_option(‘arras_options’));
It seems that previously, get_option() was returning a serialized object but isn’t anymore (this is why I prefer strongly typed languages).
The fix is simply to remove the unserialize() function from that line, resulting in this:
$saved_options = get_option(‘arras_options’);
Hope this helps !