Using HWIC-4ESW with 1841

I have a Cisco 1841 with a HWIC-4ESW card. I have set the unit up to work as expected but none of the ports on the 4ESW work. I can route to the internet on FA0/0 which is the inside interface but FA0/0/0-3 which represent the ports on the inbuilt switch do not work. I assumed initially that these ports would act just like a switch connected to FA0/0 and would need little to no configuration but it did not happen this way. I have looked at trunking FA0/0, using a BVI interface (know little about them) and building VLANs but nothing works. Devices plugged into the 4ESW work as soon as they are connected to FA0/0 but work no more when moved back to the 4ESW. Can anyone provide any feedback as to how I should configure these ports to act simply as L2 ports for the FA0/0 interface which will be the L3 port?

Thanks

This comes from using a 16 port card in this series.

No it's not like that at all.

The "switch" ports look just like the ports on a 4500 or 6500,

int vlan 1 ip address x.x.x.x /x

int 4esw-port-0 switchport sw mode access sw access vlan 1 ! above is actually default so you don't need to enter it.

int 4esw-port-1 switchport sw mode access sw access vlan 1

You can have more vlans - Don;t know about 1800.

r1#vlan dat r1(config-vlan)# vlan 2

or maybe r1#conf t r1(config)# vlan 2

anyway once that is done you can

int vlan 2 ip address x.x.y.x /x

int 4esw-port-2 switchport sw mode access sw access vlan 2 ! above is actually default so you don't need to enter it.

int 4esw-port-3 switchport sw mode access sw access vlan 2

I have no idea of the on board ports can be used as "switchports" or of they are restricted to L3. I guess restriced unless of course you configure bridging.