if this problem has already been reported, i apologize, i just haven't found another post yet.
while trying to access 'edit-tags.php?taxonomy=XXX' i get a redirect loop error.
I first noticed this for post tags, as well as custom taxonomies. problem did not exist on categories.
upon some testing, if i add a post tag (or term to any of the erring custom taxonomies), there is no redirect loop. so it seems the problem is only occurring with empty taxonomies. (category has the default 'uncategorized', so didn't have the problem)