Default Z Ultra and BT MAP


I just bought a phone that doubles as a remote dialler/messenger when paired via BT to another phone. So, in effect, you can make/receive calls as well as messages to this phone. Upon further search, the phone uses BT MAP to remote the messages. I paired it up to my Z Ultra (unrooted, 4.3) but while the remote call works as advertised, the messaging does not. Does the Z Ultra under Android 4.3 support Bluetooth MAP, or is that an Android 4.4 functionality?