[SCIP] SCIP detected infeasibility for feasible problem

[angelika.wiegele at aau.at]

Dear SCIP team,

via NEOS, I tried to solve a QP (100 integer variables, 300 quadratic 
constraints) and SCIP returned: infeasible.

However, the problem *is* feasible.
I found another way to get a feasible solution. Then I simply fixed in the 
model-file the variables to the values of this solution, and SCIP told me:

***SCIP-AMPL***

presolve, constraint Con128:
 	all variables eliminated, but upper bound = -4.54747e-12 < 0
presolve, constraint Con158:
 	all variables eliminated, but lower bound = 7.27596e-12 > 0
presolve, constraint Con34:
 	all variables eliminated, but upper bound = -1.81899e-12 < 0
presolve, constraint Con101:
 	all variables eliminated, but lower bound = 2.67164e-11 > 0
presolve, constraint Con137:
 	all variables eliminated, but lower bound = 1.22782e-11 > 0
Infeasible constraints determined by presolve.


The numbers (in the solution) are "nice" in a sense that many of them are zero 
and the non-zeros are integers in the range -100,..,100.

Question: how can I tell SCIP that 1e-11 can be considered as 0?

Best regards,
Angelika