Using Voice LAN Feature

I am moving from some old HP/3Com v1910 switches to some new Dell PowerConnect 62xx and 55xx switches.  The HPs and the 55xx's all have an "OUI" feature where I can specify the first six characters of my IP phone manufacturer's mac address so that the phone can automatically be assigned to the correct VLAN.  The 62xx switches do not have this feature however.  How do the 62xx switches know to assign a phone to VLAN 2 when the phone boots up?  Our PCs are plugged in to the PC ports on the phones themselves and they need to be on VLAN 1 so it's not possible to assign specific ports to a particular VLAN.  I'm sure that I'm missing something somewhere but I'm not sure what.

Any insight would be much appreciated.

Thanks.

-Chris