Esxi 5.1 free version + Remote Shutdown through vMA 5 (UPS)

Hi, I wonder if anybody can help me with this situation: I am using Free Esxi 5.0 hipervisor with some hosts.

Well, my boss needs to buy UPS and I done some tests with vMA-5.1.0.0-782391 (vSphere Management Assistant) and Powerchute for achieve hosts remote shutdown when the UPS starts working.

Now I need to know if this "solution" works too with ESXi 5.1 (free version) because I heard that this version comes with some critical changes.

I have little experience with vmware so I decided to ask for help here

Thanks a lot!

Tomas