[Mailman-Users] multiple header_filter_rules?

Howdy, I'm seeing the following oddity with header_filter_rules.

I have 2 rules set up. For a given test message, Rule 1 does not match, and Rule 2 does. If I have Rule 1 set to discard, and Rule 2 set to Hold, the message is discarded. If I make the single change of setting Rule 2 to Defer, then the message is accepted.

Any idea why the Action for Rule 1 is being used when Rule 2 is hit? Can anyone else reproduce this? Am I misunderstanding something about Rule processing order?

Using Mailman 2.1.9

Thanks.

-David