I just got off the phone with Kodak Professional (1-800-242-2424 option 13 - B&W gets you to the pro color division guys).
I asked about Ektar 100 in 220 rolls. He said it was possible but didn't know if it was in the plans. Every call get tracked and are reviewd by production managers.
So if you are interested in seeing Ektar 100 in 220 rolls, give Kodak a ring and ASK them for it. It can't hurt!