using ovftool for importing a .ubf (Universal Boot Format) file

Hi,

I am new to the virtualization world and was wondering if any of have come across anything like this:

I am receiving a *.ubf file from another dev group, which I successfully import via vSphere.

Now I am trying to automate this by importing the same file with the ovftool and I get the error:

"Error: Failed to open OVF descriptor"

Any help would be highly appreciated.

I.