OSPF LSA Type-3 filtering | Single ABR

I was wondering if someone can help shed some light on this situation.

I was practicing various filtering capabilities OSPF with I am came across
something that doesn't really make sense to me. It involves filtering
between areas on the SAME abr.

                 Area 0
                   |
<*R1*> -- area 13 -- <*R3*> -- area 32-- <*R2*>
Prefix =
1.1.1.1/32

This came about when I exploring the direction option (In /. out) with the
filter-list command. This following is what I suspect should have worked,
but it doesn't seem to when both the ABR is the one generating the Type-3
and is also the ABR doing the filtering...

Can someone explain why this may be the case...order of operations issue
maybe? i.e. The ABR sends its locally generated Type-3 LSA locally
before filtering them?

 ip prefix-list R1_FILTER den 1.1.1.1/32
 ip prefix-list R1_FILTER per 0.0.0.0/0 le 32
!
  router ospf 1
     *area 0* filter-list prefix R1_FILTER *out*

However all three of the following combinations work as expected:
  router ospf 1
     area 13 filter-list prefix R1_FILTER out
-or-
     area 32 filter-list prefix R1_FILTER in
-or-
     area 0 filter-list prefix R1_FILTER in

thanks

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Received on Sun Oct 27 2013 - 16:28:48 ART