Question : Router on a stick issue

so i have 2950s as my switches with 3 vlans and using vtp and trunking between them.  The main vlan the PCs are on is vlan 25.  Switching is fine.  I add a 2600 router and first of all configure fa 0/1 with an IP from vlan 25.  I plug the 2600's fa 0/1 into one of the trunk ports on one of the swtiches.  From a pc on vlan 25, I cannot acces or ping the router interface.  If I move the interface (fa 0.1) to a vlan 25 port, I can ping it.  To perform router on a stick, the router interface needs to be in a trunk port since I need to add the sub interfaces.  However, I can't even get the first one to work.  What am I doing wrong?  Is it possibly because I'm not connecting from a pc on the default vlan 1?  I wouldn't think so since I can ssh to my switches.  I'm doing somehting wrong on the router I'm sure.  Any help appreciated.  thanks.

Answer : Router on a stick issue

err sorry entered too soon

router:
int fa 0/1
  no ip address
  no shut

int fa0/1.25
  encapsulation dot1q 25 native
  ip address <ip in vlan 25>
  no shut

int fa0/1.123
  encapsulation dot1q 123
  ip address <ip in vlan 123>
  no shut

etc...