program's output from recipe script

Hi,

Does anyone know where the stdout from a program invoked from the
.procmailrc is sent to?
I know I can redirect it into a file. But if I plain simply write:

|/usr/local/bin/someprg

then where can I find the program's output? BTW I've read about the feature
for redirecting it into an environment variable, but that's not really wat I
want.

Gratefully,

--
Vik