Wrong output isRelaxationInfeasible

I just started using CyLP and I'm trying to understand how it works. The following code solves an instance of the famous subset-sum problem:

``` python
m = CyClpSimplex()
x = m.addVariable('x', 5)
c = scipy.matrix([-6,-9,11,12,13])
m += c*x == 0
m += x.sum() >= 1
m += 0 <= x <= 1
m.setInteger(x)
cbcModel = m.getCbcModel()
print(cbcModel.branchAndBound())
print(cbcModel.isRelaxationOptimal())
print(cbcModel.isRelaxationInfeasible())
print(cbcModel.primalVariableSolution['x'])
```

I expect the problem to be infeasible. The last few lines of output are:

> Clp0006I 0 Obj 0 Primal inf 0.77777768 (1)
> Clp0001I Primal infeasible - objective value 0
> Cbc0001I Search completed - best objective 1e+050, took 7 iterations and 12 nodes (0.01 seconds)
> Cbc0032I Strong branching done 18 times (17 iterations), fathomed 0 nodes and fixed 0 variables
> Cbc0035I Maximum depth 2, 0 variables fixed on reduced cost
> Clp0006I 0 Obj 0 Primal inf 1.4444443 (1)
> Clp0006I 0 Obj 0 Primal inf 1.4444443 (1)
> Clp0001I Primal infeasible - objective value 0
> solution
> True
> False
> [ 0. 1.44444444 0. 0. 1. ]

I expect the penultimate three lines to be 'infeasible', 'False, 'True'. What am I doing wrong? Is it possible to have Cbc display model statistics and supress other output?