send-hook question

["Wilkinson, Alex" <alex.wilkinson@xxxxxxxxxxxxxxxxxxx>]

Hi all,

For a particular subset of messages I need to remove a customised header. I
think I can do this via a 'send-hook'. 

e.g 

I have a customised header of:

        my_hdr X-Message-Flag: foo bar foo bar foo bar

All messages sent will have this header, however I need to *not* add this
header for a subset of email addresses. I thought this is what I would need
to do:

        send-hook bob.smith@xxxxxxxxxxxx unmy_hdr X-Message-Flag:

and any messages sent to bob.smith@xxxxxxxxxxxx would not contain the
X-Message-Flag header. This is not working.

Can someone confirm that I'm doing the correct thing here.

Thanks

 - aW