[eclipse-clp-users] Question about simple system of equations

Hello!

If some other CLP systems, like XSB or SWI Prolog, I can just write

| ?- { X + Y = 12, 2*X - 3*Y = -1 }.

X = 7.0000
Y = 5.0000

In ECLiPSe with IC library I get delayed goals with
X + Y #= 12, 2 * X - 3 * Y #= -1. (and labeling leads to 'out of range
in indomain(X{-1.0Inf .. 1.0Inf})').

X + Y #= 12, 2*X - 3*Y #= -1, X #>= 0. works.
But if I'm looking for both positive and negative roots, then I should
solve two systems, one with X #>= 0, and one with X #< 0, right?
Is there an explanation for this limitation?

Sergey.