Wake on LAN

Hi,

In our environment Wake on LAN stopped working since a while. We have a SCCM 2012 and Altiris Express server. Both has the capability to use WOL. Both serve are virtualized. We are using Vsphere 5.5 with four hosts. I know "Promiscous mode" in the security tab of a vSwitch should be "accept".

Are there any other settings in Vcenter 5.5 or ESXi 5.5, which could affect WOL to work?

Thanks,

Edy