Well first of all, your </else> should be <else />. Also the condition needs to be wrapped in quotes so the most recent revision is incorrect.
According to your Special:Version page, MediaWiki is not detecting the extension. I had the same problem and released 1.1.0 to fix it, only to realize that the hooks in vbWiki were not parsing.
In fact, I should be the only one with a working installation of this currently thanks to a bug in all current versions of vbWiki Pro. You can fix the bug by doing the following:
In
vbwiki/arcane_vbulletin_core.php, find:
PHP Code:
function arcane_vb_fetch_hook( $hookname )
{
arcane_vb_enter_vbulletin_mode();
$hook = vBulletinHook::fetch_hook( $hookname );
arcane_vb_leave_vbulletin_mode();
}
Replace with:
PHP Code:
function arcane_vb_fetch_hook( $hookname )
{
arcane_vb_enter_vbulletin_mode();
$hook = vBulletinHook::fetch_hook( $hookname );
arcane_vb_leave_vbulletin_mode();
return $hook;
}