Because IP phones running the Communicator 2010 Phone Edition support LLDP-MED (Link Layer Discovery Protocol-Media Endpoint Discovery) and PoE (Power over Ethernet), you have to utilize switches that support IEEE802.1AB and ANSI/TIA-1057 to take advantage of LLDP-MED. Similarly, to utilize PoE, the switches must support PoE802.3AF or 802.3at.
If using LLDP-MED, be sure to set LLDP-MED network policy to the correct voice VLAN ID.