Linking two PoE switches from Netgear

I've been trying to link two PoE switches from Netgear, a GS724TP and GS7728TP. When I activate the link between two switches and have the POE phone plugged in the GS728TP, the phone will not boot. If I remove the link, however, the phone boots up fine. Has anyone else had this issue? Can somebody suggest a fix for this?
