I had the exact same problem using the following bits and pieces:
- An Intel DQ77MK board
- An APC BK350EI Back ÙPS
- VMWare ESXi 5.1
- A Ubuntu 12.10 VM with the latest VMWare tools installed
The idea is to have the Ubuntu VM run an apcupsd master service that other VMs can connect to so they get a chance to do something useful in the event of a power failure. And to power off the VM host too of course.
Without thinking too much, my initial attempt at making this work had me adding a UHCI/EHCI controller to the Ubuntu VM and then passing through the APC device to that controller. It worked - almost. I also got erratic behaviour and the errors below:
drivers/usb/input/hid-core.c: usb_submit_urb(ctrl) failed
drivers/usb/input/hid-core.c: timeout initializing reports
I tried a whole bunch of things, including adding quirks options to the usbhid driver, but to no avail. Finally, while taking the VM host apart for other reasons, I discovered that the actual physical USB controller I was using was a xHCI (USB 3.0) controller. I then proceeded to change the virtual controller in the Ubuntu VM to a virtual xHCI controller too - and everything worked! No delays, no errors - just apcupsd goodness.
Realizing this is sort of an anachronism in relation to the original post, I don't know if this really helps, but I see others having the same issue elsewhere - so I am hoping this helps someone :-)