Question: simplex contradictory outputs

I am trying to solve a large system of linear inequalities (about 500 variables) subject to the nonnegativity condition on the variables.Call this system500 for future reference. I do not need to optimize any particular objective function, all I really need is one point in the feasible region.

I want to first make sure that the feasible region is nonempty so I run the command

with(simplex): 
feasible(system500, NONNEGATIVE)

It returns "TRUE" which means solutions do exist.

Next, I try to find one such solution and try

LPSolve(0,system500, assume=nonnegative)

After quite a wait, MAPLE returns the following message

Error, (in Optimization:-LPSolve) no feasible solution found

as if the feasible set is empty.

This is extremely baffling to me. I would highly appreciate a suggestion. Is there any easier way to force MAPLE to output one point of the feasible region?

Thanks.