ProTcXl has been developed primarily for ECLiPSe , but in such a way that it was still possible to include it in other Prologs. As more sophisticated features kept on being added, it was more and more difficult to keep it compatible with other Prolog systems. Moreover, SICStus Prolog v3 has its own Tcl/Tk interface and so one of the main reasons for keeping ProTcXl generic disappeared. We will therefore still keep the foreign interface of ProTcXl up to date (although it is not needed for ECLiPSe ), but we will refrain from updating code that interfaces special Prolog routines. At the same time, if some of the users write such a code for other Prologs, we will happily include it into ProTcXl , provided the additions or changes are compatible with it.