mungedomain doesn't seem to be working

[Sam Ovando <prog5CC @ oa . ptloma . edu>]

I have three RS/6000 machines:
        dopey.ptloma.edu
        sleepy.ptloma.edu
        cranky.ptloma.edu

I made sure the list.config file had mungedomain set to 'yes'.
I subscribed to the list from 'sleepy' with the following line:
        subscribe <list_name> prog5CC@ptloma.edu

It subscribed me OK, but any message I send to the list, when logged on from
'cranky' gets bounced to the owner-list as a non-recipient.

What am I doing wrong?  What do I need to do?  Oh majordomo-land, please
help me out!

TIA FAHYCGM (for any help you can give me!)
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  Samuel Ovando Jr.                 email:    prog5CC@ptloma.edu
  Systems Administrator             phone:    (619) 221-2555
  Point Loma Nazarene College       fax:      (619) 221-2581
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