What smoke are you talking about?  If you are talking about the white contrail smoke, then that should only take place above FL300.  If you are talking about the airshow smoke that should only happen when you press the "I" key or turn the smoke on from the cockpit panel.  All other smoke that I can think of is an addon and that takes editing the aircraft file.  You can ad smoke to any airplane by adding a line to the aircraft file.

Look at the extra 300 aircraft file to see the line called [Smoke] and this will give you an example of airshow smoke.

If I am way off please let me know and maybe we can think of something else.

the only condensation i know of is the one over fl300 like codered said, other than that there isnt any other to best of my knowledge