Once you've done all the trials, put The Mark of Justice in your inventory and head back to the room with Jacosh Steldenn and click on the blue portal behind him.
This will take you again to the room with the 6 The Tribunal in it. Behind each Tribunal is a blue portal. Walk up to any blue portal (don't click on the portal), take the Mark of Justice out of your inventory and put it on your cursor. Now, move your cursor with the Mark on it in front of the portal and press U on your keyboard.
This will now port you to the room with The 7th Hammer.
Edited, Sep 18th 2012 10:30am by Kenrocks

Ethereal Parchment
Faith Wrought Two Handed Sword
Headsman's Hoop
Knife of Justice
Mantle of the Accused
Precious Cameo Pendant
Steel Centered Great Bow
Symbol of Order
Warden's Buckler