Are you using MLNX OFED 2.0?
Starting from MLNX OFED 2.0, the default mode is UD.
From the User Manual section 1.3.4:
The IP over IB (IPoIB) driver is a network interface implementation over InfiniBand. IPoIB
encapsulates IP datagrams over an InfiniBand connected or datagram transport service. IPoIB
pre-appends the IP datagrams with an encapsulation header, and sends the outcome over the
InfiniBand transport service. The transport service is Unreliable Datagram (UD) by default, but it
may also be configured to be Reliable Connected (RC). The interface supports unicast, multicast
and broadcast. For details, see Chapter 4.3, “IP over InfiniBand”.
IPoIB UD performance was significantly improved in MLNX OFED 2.0, thus it was set to be the default mode.
You can still use IPoIB CM mode if you wish.
This still doesn't explain why the config in openibd.conf is not picked up, I suggest you check /etc/init.d/openibd to see if the config file is parsed as expected.