no output when wanting a passphrase

[5468696A6D656E]

gnupg 1.2.1-1 (win32)

I use pipes to communicate with a command.com window, and thus
to start gpg.
stderr, stdin, stdout are all trapped in pipes.

When issuing the command 
gpg -da -o uncryp.txt crypted.txt

i get the expected output when a key is used which has
no passphrase.

However, if the key does have a passphrase (like in a
normal situation) all i get back is a '\n'.
Nothing more in stdout and nothing in stderr.

And the program is still running.

I can't read which key it wants a passphrase for,
but while debugging i do know, because i made
the encrypted message, so i tried sending the 
passphrase as well, but still no program exit,
and no additional output. Also if i specify -v
no additional data is in output.

Any hints would be greatly appriciated.

T

-- 
__Thijmen Klok________