[Serdev] ENUM enhancements

[Juha Heinanen]

Klaus Darilion writes:

 > With the current enum resolver, I don't like the fact that I have to 
 > perform 2 ENUM lookups (=> 2 DNS lookups) for supporting both "E2U+sip" 
 > and "E2U+voice:sip).

i recall that ietf does not recommend using anything else than E2U+sip.
therefore, if you submit a patch for sip+voice:sip patch, i'll commit it
provided that it doesn't cause ANY performance penalty on the basic
lookup.

-- juha