Well it just makes sense to me. MadExcept is already configured to send to Mantis (and potentially others) so why not use it to send other bug messages rather than raise exceptions.
Anyway I have it working now.
This is the call
lSettings := NewException(etNormal, nil, nil, true, 0, 0, 0, nil, nil, esManual, nil, 0, '',true);
May be worth a blog post