Forward Address Selection/Suppression

I'm trying to make sure I understand exactly how an ASBR sets the forwarding address on a Type 7 LSA, and am not quite putting the final pieces of the puzzle together.  I'm using INEs standard ATC Workbook topology and running EIGRP between R9 and R7.  I'm setting R7 as an ASBR, and neighboring him with R3 and R6 in an NSSA. 


According to there are multiple conditions that must be met for setting the forward address to a non-zero value.  First, the next-hop interface for those routes needs to be running OSPF.  For this scenario, that would be interface E 0/1.79 (Normally Gig 1.79, but I'm running IOL)

I'm expecting R7 to set the forwarding address to, as I do not have his E 0/1.79 interface running OSPF.  In this case however, he is still setting the FA:

R7# show ip ospf int br
Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C
Lo0          1     10           1     LOOP  0/0
Et0/1.67     1     10          10    DR    1/1
Et0/1.37     1     10          10    DR    1/1


R7#show ip ospf data nssa-external

            OSPF Router with ID ( (Process ID 1)

                Type-7 AS External Link States (Area 10)

  LS age: 514
  Options: (No TOS-capability, Type 7/5 translation, DC, Upward)
  LS Type: AS External Link
  Link State ID: (External Network Number )
  Advertising Router:
  LS Seq Number: 80000004
  Checksum: 0x712D
  Length: 36
  Network Mask: /32
        Metric Type: 2 (Larger than any link state path)
        MTID: 0
        Metric: 20
        Forward Address:
        External Route Tag: 0

Why is R7, the ASBR, setting the FA for these routes?  Doesn't the interface between 7 and 9 need to be in OSPF for this condition to be met?


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