I've been curious about Curlex for a while too. It's being reformulated and repackaged, so it's not available until after 09/15/2003. (I contacted the customer services rep.) Looks like the active ingredient is this organic carboxylic acid. (Deionized water, xanthan gum, and fragrance aren't gonna straighten anything.)
Presumably the product will have been tested on various hair types before its release, but of course the first people to order and try Curlex really are guinea pigs.
The e-mail I received from the Xenna rep. promised that "Curlex is a new product and will be available on September 15th...It will be safe on lye treated hair at that time. The break down of the ingredients will be available on September as well."
I plan to try it on shed swatches of hair that I've saved from previous combouts in order to test the product. I'll post a review here later this month.
Notice my level of desperation to lay off the lye.
Meg