sp for User in a Role

From: Bruce L (bruce@Lovingscents.com)
Date: 11/25/02 

From: bruce@Lovingscents.com (Bruce L)
Date: 25 Nov 2002 13:42:02 -0800

want to create an sp_ that returns true if a user is in a role.
found sp_helprolemember, but dont know how to 'exec sp_' inside another sp and
see the result set. something like:

create proc up_IsUser
@User varchar(50),
@Role varchar(50)
as
????
if user is in role then return 1
????