funky from address

I was looking through my e-mail logs and saw an from entry that looks
like this:

from=<>

Is there an internal program that would specifically set the from
address in this way? How can I stop that from happening? I am using
sendmail.

If there is an internal program doing this, I would like to try and find
it, then change it so it IS using a proper from address and also, stop
sendmail from accepting from addresses that are not valid.

Mike

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Barsalou <barjunk@attglobal.net>
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