I thought burning oil typically put off black smoke...and white smoke was usually a sign of antifreeze/coolant burning..?
What do I know though...I'm an IT guy, LOL.
EDIT: Check this site out:
http://wiki.answers.com/Q/What_can_c...om_the_exhaust
There's a lot of information, and some contradictions, but these two struck me as a possible culprit/fix for you...it sounds similar:
"- My problem with white smoke was whenever I would be going down the road at high RPM and let off the trottle. Then it was like a smoke bomb went off. Bottom Line.......... My Vacuum Modulator went bad on my transmission whenever high vacuum was created it was sucking transmission fluid into my intake manifold and thus into my combustion chamber creating white smoke. Replaced the modulator for $12 and everything is right with the world
- I had the exact problem with my Mazda down to a T. All we had to do was buy a bottle of engine sealant... it takes a full day to run thru so follow directions exactly. Now the car has no problems... full power is bacl no more "smoke bombs" and no more dying at strange times."