From the external DNS on Mail in a box
SRV 0 0 443 box.hollywood-ent.com
is the 00 443 the port number?
In your example …
_carddavs._tcp.domain.com SRV 0 0 443 box.hollywood-ent.com
_carddavs is the service name
tcp is the protocol
@ would be the entry for name (the method CF uses)
0 would be the priority
0 would be the weight
443 would be the port
box.hollywood-ent.com would be the target.