The docs state that the error mode is either fatal or output with no in between. I guess you could sub-class the constructor and re-write the fatals sub to do both.
in reply to Re^2: Mason error capturing
in thread Mason error capturing
The problem, I guess, is that the error is (usually) during the interpreter phase, and doesn't get anywhere near your code, so you can't do anything too fancy. You could, of course, write a PerlLogHandler module that lets you know when an error's occured via email or somesuch.