There was a discussion while back on this topic. You might check the
archive files. Someone on the list offered (via snail mail) a copy of the
"IRS 20 Rule Test" for making this determination based on the requirements
of IRS ruling 87-41. I'll FAX a copy to you.

Bruce W. Steinert, Ph.D.
Department of Urology
William Beaumont Hospital
3601 West Thirteen Mile Road        (810) 551-2572 (Voice)
Royal Oak, MI  48073-6769           (810) 551-8107 (FAX)