VMware Tech Support have come back with the following:
"It appears that the drivers required are:
cnic version 1.74.04.v50.3
bnx2x version 1.74.22.v50.1
And the firmware version required is 7.4.22."
Two further questions:
1. Is the firmware version of 7.4.22 upgraded through HP SUM / SIM ?
and just to be clear...
2. the firmware that is getting upgraded is the Blade's onboard NIC (Mezz card ?)
Thanks