Problems when IXFR request comes in and no ixfr available

Starting situation:
signed slave has SOA 1303344380
ODS signer has nothing (working directory cleared out)

ODS then signs zone (Would be good if the logs had a SOA number in them!)
Signed slave requests IXFR and gets this:
failed while receiving responses: tsig verify failure

This response is not correct as the tsig is correct. Doing "rndc retransfer example.com" transfers the zone correctly.
New SOA was higher than previous one on signed slave - 1303345739, so, with no IXFR to fall back to, and AXFR should have been allowed/performed.

ods-signer logs contain this:

[axfr] unable to open ixfr file example.com.ixfr for zone example.com
[axfr] axfr fallback zone example.com
[socket] unable to handle outgoing tcp response: write() failed (Broken pipe)