I give Jaheira:

Belm +2 (gives an extra attack per round). Water's Edge +3
Gauntlets of Binding Strike (Improved Haste).
Girdle of Hill Giant Strength.
Boots of Speed.
Harper pin (Finally of it from Elminster).
Ring of Gaxx
Ring of Protection +2
Red Dragon Armour
Ring Fire Control
Helm of Defence
Clock of the Sewers

At level 13/14 Jahiera has 9/2 attacks per round. Does 16-60 damage per hit and never misses a hit. She's very hard to hit and fights almost as good as Drizzt's.

Bad assed mofo

That would be pretty good on an unmentioned half orc barbarian we all know about.

Odd party member to beef up like that and give the ring of Gaxx to, but OK. Otherwise, it's kinda(no boots speed or dual wield or 19 str, only 18/00 with gauntlets ogre power) like my fighter/druid. I gave her the dusty red ion stone and cloak +2 as well, boots of etherelness, shield +4, frostbrand, and shield amulet. Actually, now that I think about it, it's not a lot like my PC after all. But still good :) Actually better judging from attacks and damage point of view. But not every party member can fight like a tank.

I think In the game to have a powerful and well balanced party, you need atleast 3 tanks, one cleric, one mage and a thief.

Jahiera being beefed up like a tank and a healer who can summon animals makes her awesome in combat.

Firstly, 3 rings? Good trick. :)

Secondly where does this pin come from and how did you meet Elminster?

Where'd ya get the Clock of the Sewers from? I once got ahold of an item called the Wristwatch of the Outhouse, but the item's only ability that's worth speaking of is that it beeps about 5 minutes before I'm about to suffer from explosive diarrhea.

Elminster is the one that gives you the harper pin. ;)
You have to do the harpers Jaheira subquest for this.

You get cloak of the sewers, brace for impact, IN THE SEWERS. Doh.
I think in the ones beneath Copper Coronet.

sorry under the temple district.

and anyway take a real fighter(or barbarian),
give him those items,make him(or her)a grandmaster with scimitars,give him 3proficency-pionts in dual wielding and you'll get to know the real meaning of the word tank