Another good one:
...
version message: version 40000, blocks=174571
04/06/12 21:31:23 received: verack (0 bytes)
04/06/12 21:31:23 received: block (7123 bytes)
received block 00000000000008506c9e
SetBestChain: new best=00000000000008506c9e height=174572 work=286071818980138056873
ProcessBlock: ACCEPTED
04/06/12 21:31:23 received: inv (37 bytes)
got inventory: tx 2218b46d9523b7a39653 new
askfor tx 2218b46d9523b7a39653 0
sending getdata: tx 2218b46d9523b7a39653
04/06/12 21:31:23 sending: getdata (37 bytes)
04/06/12 21:31:23 received: block (7123 bytes)
received block 00000000000008506c9e
ERROR: ProcessBlock() : already have block 174572 00000000000008506c9e
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 sending: addr (31 bytes)
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 received: inv (37 bytes)
got inventory: block 00000000000008506c9e have
askfor block 00000000000008506c9e 0
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 sending: inv (37 bytes)
04/06/12 21:31:23 received: tx (620 bytes)
Rate limit dFreeCount: 728.562 => 1348.56
AcceptToMemoryPoolUnchecked(): size 5
AcceptToMemoryPool(): accepted 2218b46d95
04/06/12 21:31:24 received: inv (37 bytes)
got inventory: block 00000000000008506c9e have
askfor block 00000000000008506c9e 1333747883000000
04/06/12 21:31:24 sending: inv (37 bytes)
04/06/12 21:31:24 sending: inv (37 bytes)
04/06/12 21:31:24 received: inv (37 bytes)
got inventory: tx 2218b46d9523b7a39653 have
04/06/12 21:31:24 sending: inv (37 bytes)
04/06/12 21:31:24 sending: inv (37 bytes)
04/06/12 21:31:24 sending: inv (37 bytes)
04/06/12 21:31:25 received: inv (37 bytes)
got inventory: tx 2218b46d9523b7a39653 have
04/06/12 21:31:26 sending: inv (37 bytes)
04/06/12 21:31:26 Flushing wallet.dat
Flushed wallet.dat 19ms
04/06/12 21:31:26 sending: inv (37 bytes)
04/06/12 21:31:26 sending: inv (37 bytes)
04/06/12 21:31:26 received: addr (5851 bytes)
Segmentation fault
The returncode is 139 at this point.
Note how at one point is sais received block 00000000000008506c9e, then it sais error, already have 00000000000008506c9e. Then shortly after it sais ask for block 00000000000008506c9e and shortly after it just segfaults.
Edit: added code tags