  We give a combinatorial description of the Legendrian differential graded
algebra associated to a Legendrian knot in PxR, where P is a punctured Riemann
surface. As an application we show that for any integer k and any homology
class h in H_1(PxR) there are k Legendrian knots all representing h which are
pairwise smoothly isotopic through a formal Legendrian isotopy but which lie in
mutually distinct Legendrian isotopy classes.
