Hi Benjamin,
Assuming your connecting the Aironet AP to one of the lan interfaces then what I would suggest you do is create the vlans on the 867, Then setup SVI's for each vlan and let these deal with your layer 3.
So example would be
conf terminal
vlan 10
Name test1
vlan 11
Name test1
vlan 12
Name test1
interface vlan 10
ip address 192.168.10.1 255.255.255.0
no shutdown
interface vlan 11
ip address 192.168.11.1 255.255.255.0
no shutdown
interface vlan 12
ip address 192.168.12.1 255.255.255.0
no shutdown
interface Fa0
description Connection to Aironet
switchport trunk encap dot1q (This command may not be needed)
switchport mode trunk
switchport allowed vlan 1,10,11,12
I hope this example helps.
You will need to setup the aironet AP interface as a trunk and add a vlan for management or use vlan 1 if you are that way inclined.
Your router may have a limit on the number of vlans some have a limit of 4 or 8 including vlan 1