Can Voip incoming call wake the computer from sleep?

If a Mac is asleep and no other programs except a softphone app is
open, and the computer sleeps and someone rings the VOIP access number
(that works fine when the computer is awake), will ticking 'Wake for
network access' in Sys Prefs/ Energy/Power Adapter (Snow Lep) wake the
machine and enable the softphone to ring?