Milter-greylist

Hi,

I've been using this version of milter-greylist for some time (I know 
there's an upgrade but haven't had time to upgrade yet).

Most recently I've been making mods to the greylist.conf file one on server 
which gets synced to all MX servers, and I get milter-greylist crashing when 
it performs a reload:

Dec 25 09:55:55 server milter-greylist: reloading config 
file "/etc/mail/greylist.conf"
Dec 25 09:55:55 server sendmail[2670]: lBOMtMJN002670: milter_read
(greylist): cmd read returned 0, expecting 5
Dec 25 09:55:55 server sendmail[2670]: lBOMtMJN002670: Milter (greylist): to 
error state
Dec 25 09:55:55 server sendmail[2721]: lBOMtR2R002721: Milter (greylist): 
write(D) returned -1, expected 156: Broken pipe

I then have to stop mail services on each server, restart milter-greylist 
and then start mail services again.

I run 4 inbound mail servers which use this milter-greylist version and they 
all do the same thing.

Any ideas what the "cmd read returned 0, expecting 5" means or should I 
spend the time upgrading to 4.0 stable?

Thanks.

Michael.