I asked for (and immediately received - Thanks!) some assistance via the Drools IRC webclient regarding throwing exceptions inside rules.
I now know that this is probably a bad thing in most cases, however one of my queries at the time was how to stop the stacktrace being sent to the console even though the exception was successfuly caught at the .fireAllRules() invocation.
It was suggested that this was a bug, and could I submit a JIRA - here it is.
Attached is a very basic re-create of the situation. I'm running Drools 4.0.4.
As I've managed to convince my team mates that throwing exceptions from inside rules is a bad thing, I won't be waiting for a fix
Thanks for a great product,