Hexagon had a turtorial on how to create and rig clothes for poser. Looked like could be done with any modeling program as most the rigging work is in poser itself. As I don't use hexagon I don't have the tut to look up. You may find on their site though.
Found this, may be of some help also.
http://forums.polyloop.net/hexagon-tutorials/9083-creating-conforming-clothes-hexagon-2-poser-5-6-a.html
Edited by harrgunn on 10/01/07 03:10 PM.