shares via vpn vista

Here is my setup.
Netgear vpn router at home. Using vpn client software on Windows xp
sp2 to access and establish the vpn router. Connection is successful
and I can ping all the machines on the other side of the router. I
can
access share on windows xp machines, windows 2000 server machine but
I
cannot access shares on any vista machines. Connection attempt times
out. The shares are there and can be accessed locally.
Any ideas?
Thanks in advance!