I don't know why, but if you want to check kodak's page here is the link to the XTOL description: http://www.kodak.com/cgi-bin/global/en/professional/webCatalog.pl? cc=US&lc=en&product=XTOL+Developer,+KODAK(posted 8794 days ago)It is indeed ascorbic acid. Not so strange to me anymore after I read here that you can use cofee as a developer as well :^)
The best thing of it is that it is environmentally safe.