IIS and unicode

[aliver vilereal <willey () BLUE NET>]

ok,
is it true that the unicode exploit only works under foreign machines that use 2-byte characters?  if so, how can i 
check (in a http response) if this is a vulnerable system.  i have heard that english systems are also vulnerable, but 
require a differnt string to be passed to them, is this true?

thank you for your help

aliver vilereal
ubermother