When I run 5.1i Timing Analyzer in stand-alone mode on Virtex-II designs, the following messages appear:
"Voltage prorating is not available for this device and speed grade."
"Temperature prorating is not available for this device and speed grade."
Once I open Timing Analyzer, these options are grayed out.
Virtex-II does support voltage and temperature prorating in ISE 6.1i.