Jah does not affect ANYTHING you would wish to MF, so I would recommend something else. The best thing it would help hit is Champions...

Sur won't matter, as you'll be within their view whether blinded or not if you melee.

Um is OK. Say your pally is lvl 85, the Open wounds will casue it to lose 9.79 HP/Frame (That's 245 damage/second for 8 seconds). It's free damage, so it could be useful. However, if you have a high zeal rate, a 40/15 max may serve you just as well.

Lo is excellent for the Deadly Strike.A high chance to deal double damage is VERY worthwhile, so I'd recomend 1-2 Lo's in the weapon.

Mal works on everything, from what it looks like. It's your call on that one, but I'd say nah.