Process substitution in bash - doesn't work

[Herculano de Lima Einloft Neto]

     Hello all,

     Whenever I try something like vi <(diff file1 file2) in bash I get 
an empty file on /dev/fd/63.. is there a way to make it work? Or does 
FreeBSD not support this?

5.1 RELEASE

TIA,
--
Herculano de Lima Einloft Neto <hlen at ig.com.br>