Described herein are various approaches that allow rules to be used to specify actions, that alleviate the complexity and burden of developing and maintaining rules in a rules-based messaging system, and that provide more efficient ways of evaluating rules. The approaches allow rules to specify user-defined...http://www.google.co.uk/patents/US20040030707?utm_source=gb-gplus-sharePatent US20040030707 - Partial evaluation of rule sets
