I've heard alot of good story's about the Kensai-Mage and the Kensai-Thief, is there anyone that tried a Kensai-Cleric? I think they can get pretty powerful in melee when using the staff of the Ram and some protection spells.

I have never really tried this combination. But to be honest I dont think it would be a good Idea as the kensai is a warrior of the sword and gets huge bonus's for using one and the downside is that you cannot use armour. So if you dual to a cleric you wont be able to use swords or armour so there aren't any advantages to the class.