DKIM temperror's from yahoo

I'm hoping someone here has some experience with sending DKIM signed
messages to Yahoo. We are successfully signing our outbound emails, and
Gmail is accepting the signature:

Authentication-Results: mx.google.com; spf=pass (google.com: domain of
FollettTextRental_at_fheg.follett.com designates 12.171.92.143 as permitted
sender) smtp.mail=FollettTextRental_at_fheg.follett.com; dkim=pass
header.i=_at_fheg.follett.com

However, Yahoo is saying the DKIM authentication is failing with a
"temperror:"

Authentication-Results: mta1098.mail.mud.yahoo.com
from=fheg.follett.com; domainkeys=neutral (no sig);
from=fheg.follett.com; dkim=temperror (multiple keys)

Has anyone seen this error? We are only publishing one key in DNS, so
I'm not sure what "Multiple Keys" is referring to. I can't seem to find
any information about this on the web.

Any ideas would be greatly appreciated.

Here are my DKIM and DKIM Policy records published in DNS:

062010._domainkey IN TXT "k=rsa\;
p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC6uR/xej8OnYH09R8GjxZVygaUrT/xWO
qyGE10ELxOe5biYWE9IZexZm53NuRXyLZHJzSQZA3UIZcj3XZJ/aOAOhDX3Tov0+Vkj/JG6N
Y6GUv4wRB6Cdd42bzOd2i3NEJVL54V5+n+yfWy9her9bOohEr0U5jmg6jQfKKMjg2N+QIDAQ
AB" ;New DKIM Record

_domainkey IN TXT "t=y; o=~;" ;DKIM Policy
Record (not all emails are signed)

Thanks,

Josh
Received on Thu Sep 02 2010 - 14:59:26 PST