1. A computer-implemented method for complex event handling, comprising: providing, within a complex event handling system, a rule implementation system; providing, separately from the rule implementation system, an event log operable for maintaining a history of past events and associated prior event parameters for future rule testing; receiving, by the complex event handling system, a current event; storing, by the complex event handling system, the current event to the event log; matching, by the complex event handling system, the current event against rule conditions within a rule implementation system; identifying, by the complex event handling system, rule conditions, within the rule implementation system, wherein those rule conditions depend upon both the current event and the past occurrence of a particular prior event; searching, by the complex event handling system, the event log for the particular prior event; retrieving, by the complex event handling system, prior event parameters, from the event log, corresponding to the particular prior event; evaluating, by the complex event handling system, the rule conditions in view of the current event and the retrieved prior event parameters; and executing, by the complex event handling system, actions corresponding to the rule conditions triggered in response to the evaluating.