No. The +3.3V supply coming from the Duemilanoves and earlier boards came directly from the FT232 device and was limited to only 50mA, not protected, etc. so it's best to not even count on it being there. If anything I'd recommend a design technique that uses a single regulator on the shield itself, derived from the 5V supply.
On the Uno's you have a proper 3.3V regulator so you could ask it to share the load current by playing tricks with resistance, but why solve a problem that doesn't exist?
The Aussie Shield
: breakout all 28 pins to quick-connect terminals