[Exim] system alias to pipe

I want to set up a system alias that pipes the message to a
command. How do I do this?

I've stuck the following in my /etc/exim.conf

> mycommand_aliases:
> user = nobody
> group = nogroup
> driver = aliasfile
> file_transport = address_file
> pipe_transport = address_pipe
> file = /etc/aliases.mycommand
> search_type = lsearch


After restarting exim (running in daemon mode), when I send a
message to the alias, I get "Neither the system_aliases director
nor the address_pipe transport set a uid for local delivery
of | command".

I have majordomo running with a very similar .conf entry
except that mycommand is replaced with majordomo and user
and group are majordom.

Have I missed a step somewhere?

Thanks,
Dee Jay

+-----------------------------+------------------+-----------------------+

| Founding Partner            | Software Engineer| Dee Jay Randall, B.Sc.|
| Circular Reasoning          | Accrue Software  | M.Sc. Student, CS     |
| randal@???| www.accrue.com   | ICQ # 43551676        |

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