I'll check my tin tomorrow, but if it is, then surely the solvent is the carrier for the active ingredient and will evapourate off completely? I'm sure it must act in the same way as solvent based glues work, they carry the active ingredient to stop it setting and making it easier to apply then it evapourates off. I've used Thompsons waterseal for years on dpm's, tents and the like and I was around fires and stoves daily when I worked on my last big felling project and i never went up in a flash!
I have yet another question regarding this tent, what are people going to be using to sleep in this tent? being exact. E.g im thinking, using an old DD 3x2 tarp as a ground sheet. ontop of which I am putting a Gelert single air matress (13 quid on ebay! + FREE P&P thats a bargain if you ask me, just thought id give you a heads up.) then ontop of that ill have in my sleeping bag a 3/4" foam mat, ontop of that mat a very thin double bed duvet, folded in half so that one half is below me the other ontop. Think i'll survive the cold
EDIT:
Pic of airbed;
link to item:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=160360573979&ssPageName=STRK:MEWNX:IT
The first 3 are Bottle Clearly Marked. I think you can guess the last one.
It would take quite some stitching (my needle work makes Herr Doktor Frankenstein look like a seamstress) so adhesive might be the way.
I'm going to try a 'lacing' system/method when I get out with it next week. If it works as a trial I'll post it up.