I am surprised its not on cable movies yet

Not yet. The film should be covered by the deal Paramount had with Showtime until the end of 2007. Showtime frequently sits on films for a long time after their theatrical release before they run them - up to two years. Showtime did just that with Lara Croft Tomb Raider - The Cradle Of Life. (The usual pay-cable window for a film is 10-13 months after its theatrical release; Starz sometimes plays a film nine months after its theatrical run.)

UPDATE-Showtime will premiere this film on Friday, February 13, 2009 at 7 p.m. It will be available On-Demand for the following 28 days. They've started promoting it on the channel.
http://www.sho.com/site/schedules/product.do?episodeid=132087&seri esid=0&seasonid=0

BRING OUT SEASON THREE OF THE GREAT ONCE AND AGAIN ON DVD!

In case you didn't know, it is now on Showtime. I know your post was a long time ago, but thought I would let you know.