They said a modified version was used by him in the Deutschland Tour...aluminum modified by the looks of it
BTW, anyone notice the darker Shimano cranks?
I'm quite sure there were stages when he used the alum custom while in others he used a Giant composite - the simplest way to be sure is looking at the chainstay. Carbon seatstays from giant always connects to the main structure before smoothly joining to the seattube. While the alum seatstays are always welded indepdently to the seattube.
On certain stages Ullrich would be on one - then on others the other. in TdS he was on a composite bike the entire time.