JFFNMS (http://www.jffnms.org) seems to have a decent SLA configuration.
Been working for us in a limited testing capacity.
Regards,
Jade
Jade E. Deane
Senior Network Engineer
SunGard Futures Systems
SunGard Systems International, Inc.
jdeane@sungardfutures.com
+1 (312) 577-6100
+1 (866) 741-0076 (Fax)