The only truley effective process I've found is ozone. This will eliminate the smell of smoke rather than just mask it. We have used this technology on tables that have been in smokey pool rooms for years and it really does the job well. It also eliminates mold, mildew and most organic smells.
I've posted a link, many company's sell and rent this equipment, try your local yellow pages under air purifiers, just make sure its using an ozone generator as the primary decontamination process.
http://www.air-zone.com/removesmoke.html
Jay