[eclipse-clp-users] Problem with double delayed negation

Dear all,

I stumbled across a problem using delayed negation (~/1, ~=/2).
The following small program demonstrates my problem:

%%
p(_X) :- A~=1, A=1.
p1 :- ~ p(1).
p2 :- ~ p(X), X=1.
%%

?- p1. succeeds as it should, but
?- p2. fails despite being equivalent to p1

Is this a bug? If not, is there any way to make p2 work as expected?

Btw, the bugs database (http://www.eclipseclp.org/bugzilla) is down.

Best regards,
Stephan