Where does it say the bike is steel??? If the frame is alu and the post is alu, then heating the seat tube - NOT the post! - with a propane torch should cause it to expand more than the post. Otoh - goodbye Mr Paint! And you'll need to keep the heat way down to avoid interfering with any heat treatment the frame had.

This is what Sheldon Brown suggests:

http://www.sheldonbrown.com/stuck-seatposts.html

Btw, you might want ti read this -

- Not that I'm trying to put you off! (Also: HOW do you die removing a seatpost??)