Asterisk ignoring replayed libpcap sessions

Hey,
I'm currently testing the Asterisk PBX for vulnerabilities but I just
encountered an interesting problem when trying to recreate a crash.
Using a fuzzer I can crash it in the exact same place every time. I am
recording these session using ethereal (wireshark) and then replaying
them using tcpreplay e.g

sudo tcpreplay -i lo dieAsterisk.eth

Anyways, the problem is Asterisk completely ignores the data sent to
it via tcpreplay. I'm not sure what the issue could be. The packets
replayed are identical. Is anyone aware of any checksum that takes
timing into account or whatnot in Asterisk?

Thanks,
nnp

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