The Monitor did not respond to the test request

Hi folks,

I have OPManager 6005 running on Windows XP and a 3 Phase Powerware 9355 UPS .

I want to setup monitoring of this UPS using OPManager.

Because OPManager doesn't nativly support Powerware I planned to use "custom monitors". So I loaded a program called "MIB Browser" from ireasoning software house. I can successfully get info back from the UPS using this MIB browser. The OID's I'm really interested in are the "output current of each phase". So in the MIB browser if I enter the oid...
.1.3.6.1.4.1.534.1.4.4.1.3.1 I get the current value of phase 1
.1.3.6.1.4.1.534.1.4.4.1.3.2 I get the current value of phase 2
.1.3.6.1.4.1.534.1.4.4.1.3.3 I get the current value of phase 3

If I enter these oid's into 3 custom monitors within OPManager they don't work. When I do a test I get back the error "The Monitor did not respond to the test request".

Anyone any ideas?

thanks
Dave