[mpop-users] filter in .mpoprc

Not quite sure if this is the correct place to ask this. I apologise in advance if not.

I've been using mpop for quite a while. Big fan. Does exactly what I want.

Now I'm trying to use the filter command. That is in my .mpoprc I want to call a bash script, which either exits with code 0 or 1 in order to retrieve or kill the mail.

So I have a line in .mpoprc like:
filter /home/vhosts/myfilterscript.sh

Which I should think would call my bash script "myfilterscript.sh" and would have an effect depending on the piped header.

My problem is that my script does not seem to be called at all. Checked this by letting the script write something to log on calling.

And obviously no filter action is taken either.

Tried somehting like:

filter /bin/bash /home/vhosts/myfilterscript.sh

Maybe something to do with it being a bash script.

Even strange constructs like:

filter if [ "`bash /home/vhosts/myfilterscript.sh`" ]; then exit 1; else exit 0; fi

And yes the script is executable. When run direct from prompt it performs as expected (returning either exit 1 or exit 0).

Probably I'm overseeing something complete simple or obvious, but I've googled and searched and haven't found a solution.
So any help would be appreciated !

BTW.

This script checks against as set of names in a file against the From in the header, and rejects accordingly.

Effectively having some sort of blacklist functionality when using mpop to retrieve mail.

It would just kill, and not retrieve at all for email-senders defined in my file.

If this is completely stupid because it can be achieved in a simpler way... please tell me.

Kind regards,

Joost