Can I extend a Vlan thru serial ports omitting IP's?

[hchaikin]

The default gateway for my 138.45.221.0/24 LAN is Vlan221 on my Cat6509 (w/RSM) I need to extend this vlan out my fast serial port 3/0/2 where it will be extended via pairgain modems. The distant end of this T1 terminates on S0 of a 4000 router which, in turn, is connected (thru Eth0) to a unix host that needs to be a member of vlan 221, remotely. Can I configure the 6509 and 4000 so that the default gateway for this host remains vlan 221 on the 6509's RSM?

[mgnordhoff]

As long as both serial ports are configured for vlan "trunking" you should be fine. A VLAN is layer 2 functionality so IP addressing on the interface is irrelevant unless you want to be able to ping or telnet to the physical ports.