I used "Automotive Goop" from WalMart about 6-7 years ago. You have to clean it really well with alcohol, then glue it down and use masking tape to hold it for 24 hours. Mine has never again come apart. I think I paid $6 for a tube of it. http://eclecticproducts.com/goop/ad_automotive.asp
3M weatherstripping adhesive (get it in black, not yellow) works great for D and rib seals. Maintains flexibility also, so it should work well for this instance.
Windshields are held in with sikaflex (cars/RV's/etc all use sikaflex I believe) and that is another option. It comes in caulking tubes so you will need a caulking gun (cheap). If you have a portable heater, it would be wise to heat the sikaflex tubes up before you use it. It makes it much easier to apply. It's usually the ONLY thing holding a windshield in, and obviously works wonders. It also maintains flexibility but more so than the 3M stuff.
Personally, sikaflex is the way to go. Just make sure both surfaces are very clean before so you get full adhesion.
Scott
I went to a upholstry shop & got some of this black window adhisive, don't remember the name. Prep work is the key to how long it will last. Mine has lasted over 3 years.
My top was delaminating at the base of the rear window. Took it to an upholstery shop; the tech there said there was no problem with leaks but the window was heat sealed to the top at the factory, and to his knowledge there was no "fix" other than to replace either that section or the whole top. I didn't like that option for what appeared to be about 18" of loose fabric that had no impact other than a cosmetic one.
After reading on this forum and some other forums on cars with convertible tops, it appears a urethane based adhesive is the way to go.
My son worked for a windshield repair guy while he was in college. The guy put some primer on my glass, then applied the urethane, taped the two surfaces together, and advised me to leave the tape in place for 48 hours.
Not sure how long it will hold, but I removed the tape this a.m., and it appears to be holding very firm for now. Time will tell, but at least I have nothing invested, and I think it's going to do fine.
Just an FYI; at least in my area, the primer and the urethane are both available at car paint shops. Urethane was around $19 for a tube that fits in a regular caulk gun; the primer was $35 for a very small bottle. Both would do many, many windows with this problem.