VNC thru Linksys VPN

[tuxis :):):)]

   Greetings,

   PROBLEM:   connecting  to  Linux server from Laptop (when outside LAN)
   using VNC through VPN Router.

   When directly on the LAN, VNC connects from Laptop1 to Linux1 thru VNC
   without problem.

   When  outside  the  LAN,  I  can  connect  to  WinXP1 using PCanywhere
   (through the VPN) without any problem.

   When outside  the  LAN and  trying  to  connect from Laptop1 to Linux1
   using VNC through VPN, the connection fails.

   I  have  read the VNC FAQs, troubleshooting steps and previous mailing
   list  questions  similar  to this issue to no avail.  The only obvious
   (to  me) troubleshooting step I have not tried is connecting to Linux1
   directly  over  the  internet  using VNC.  I believe the problem is in
   router  port  forwarding  but  am  a bit concerned with opening ports.
   Wouldn't opening extra ports defeat the purpose of having VPN?

   Regards,

   Darren