[Exim] Pipe delivery to a program gives error

     I have the typical 'error 69' delivering a message to a pipe via
the correct driver, that is covered by the FAQ. I already read it, but I
can't find the origin of the problem. Let's see an example:

    program_delivery:
      driver = pipe
      command = '/bin/cat >> /export/home/nobody/one-file'
      user = nobody
      group = nobody

    When I send a mail that goes thru this driver, I have the following
error:

    ** ejecutar@??? D=comando_unix T=program_delivery: Child
process of program_delivery transport returned 69 (could mean service or
program unavailable) from program: "/bin/cat >>
/export/home/nobody/one-file"

    Thanks,

        Manuel Molina Cuberos / http://easy.to/deluxe
        IP Sistemas           / http://www.ipsistemas.com