Milter-greylist

Hello,

I'm running milter-greylist-1.6rc1 with libspf_alt-0.4.0 on multiple 
RHEL3.0 with sendmail 8.12.11 and bind 9.2.4rc6

I'm seeing lots of entries in maillog like these:
Milter (greylist): timeout before data read
Milter (greylist): to error state

My guess is that sendmail times out waiting for milter-greylist to 
complete something, possibly SPF queries?

What can be done to fix or limit these errors?

Regards, Tony

ps: I've seen other milters with timeout values in sendmail.cf  but cant 
anyting of the like for milter-greylist