automatic tables / self statement in pf.conf

[mike tancsa]

I have a process that runs every few min looking to see if the pf rules
changed on some of our firewalls.  On one customer unit, we have a
"self" statement and the script detected a change this morning.  The
rule reads

block log quick from <rejects> to self
block log quick from self to <rejects>

but when shown it looks like

block drop log quick inet from <rejects> to <__automatic_32a5c00f_0>
block drop log quick inet from <__automatic_32a5c00f_1> to <rejects>

I guess 'self' is treated like a table ? The diff that got flagged
looked like

-block drop log quick inet from <rejects> to <__automatic_786310c4_0>
-block drop log quick inet from <__automatic_786310c4_1> to <rejects>
+block drop log quick inet from <rejects> to <__automatic_32a5c00f_0>
+block drop log quick inet from <__automatic_32a5c00f_1> to <rejects>

What would trigger the table name to change like that ?	

Also, is there a better way to monitor pf rule changes ?  I dont see any mention in FreeBSD audit ?

	---Mike