I think the best thing to do would be add an error event aswell, and have them it triggered just 'above' the default error-handling. So when an error occurred it would go through these steps:
current alias' error jump-point code.
propagate through calling aliases' error-handling code.
call script error event(s).
mIRC's default error-handling code.
And of course allow /reseterror to halt the error-handling at any point. This way you can have alias-specific handling and/or generic handling.
Really this thread should be in Feature Suggestions though, since whether you like $error or not, you can't consider it a bug.
