Known Bugs and Limitations (SICStus Prolog Release Notes)

Jasper cannot be used from within applets, since Jasper relies on calling methods declared as native. This is due to a security-restriction enforced on applets by Java; they are not allowed to call native code.
Some uses of SPTerm will leak memory on the Prolog side. This is not really a bug but may come as a surprise to the unwary. See SPTerm and Memory in the SICStus Prolog Manual.
Loading multiple SICStus runtimes has not been very well tested with multi threaded Jasper.