Netware 6.5 SP5

I'm trying to configure fail over for a new HP MSA1500cs we have, I can get it to fail over once but when it does it looks like Netware is disabling the disk on the path that fails. A SCSI CDM error on the console says the disk device has failed and it is being disabled. At this point everything is ok as the passive path is now the active path. This is fine until we try and fail back, at which point the original active path no longer exists within Netware and the volume is dismounted/data lost.

I can't understand why, if MPIO is enabled it is disabling a path, surely it must understand that paths become unavailable for periods of time?

I have set "SET MULTI-PATH SUPPORT = ON" in the startup.ncf
I have set "LOAD QL2X00.HAM SLOT=3 /LUNS /ALLPATHS /ALLPORTS" when loading the driver
before failover; Using iManager - Multipath, I can see both paths and have set priorities for both paths, the original active being 1 and the passive being 2.
after first failover, iManager only shows one path

The server has a single HP FC2214 (QLA2340) card with a single port.
The MSA1500cs is ACTIVE/PASSIVE latest 5.20 firmware
A HP 4/8 (brocade 200E) fibre switch is being used, zoning is configured, one zone is configured for the netware server to see both controllers on the MSA1500.

Can anyone help, as far as i can see this should work, I don't understand why the SCSI CDM is disabling the disk(path/lun) on failover.