Agreed -- appears to be MySQL5-related.

Just taking a quick stab without testing:

/includes/classes/sel.url.php
around line 912:
Code:
							FROM ".TABLE_CATEGORIES." c, 
							".TABLE_CATEGORIES_DESCRIPTION." cd 
							LEFT JOIN ".TABLE_CATEGORIES_DESCRIPTION." cd2
Try changing that to:
Code:
							FROM ".TABLE_CATEGORIES_DESCRIPTION." cd, 
							".TABLE_CATEGORIES." c 
							LEFT JOIN ".TABLE_CATEGORIES_DESCRIPTION." cd2