Mainey,
Have you had any other speeding fines in the last few years?
If not, write a letter to them, acknowledging the offense, say you're sorry, tell them you are normally a good driver, and ask them to please reconsider.
They will hopefully re-issue you with a warning instead.
It's worked for me (twice), the wife (once), my dad, and two of the guys here at work (plus the wife of one of them) whom I told about this unwritten 'loop hole'.
As long as you're not more than 10k's over the limit and haven't had a fine for a year or so, it works.
It may only be a Vic thing but give it a go... you've got nothing to lose and everything to gain.
Oh and I'm not gonna take the high ground and tell you to not speed as I live in a 'glass house'. It'd be hypocritical... of me anyway.
LJ