Numerical errors in mtl/lapack (solving a linear system of equations with getsv)

Assume I try to solve the  linear system with A=
[1,1,2 ],
[2,2,2],
[2,2,1         ]
and b:
[15],
[15],
[15]

obviously I get an error (A is singular and with this b there is no 
solution). In fact getsv returns:

> Factorization failed with INFO = 2

However if I change A to
[1,1,2 ],
[2.1,2.1,2.1],
[2,2,1         ]
I get a solution!:

> A:
> 3x3
> [
> [1,1,2],
> [2.1,2.1,2.1],
> [2,2,1]
> ]
> b:
> 3x1
> [
> [15],
> [15],
> [15]
> ]
> x:
> 3x1
> [
> [-2.16004e+17],
> [2.16004e+17],
> [5]
> ]
> A:
> 3x3
> [
> [2.1,2.1,2.1],
> [0.952381,2.64545e-17,-1],
> [0.47619,0.5,1.5]
> ]

This is clearly an error. Did anybody noticed it before?
thanks,
fabio schoen

-- 
----------------------------------------------------------------------------
Fabio Schoen  		Professor of Operations Research
tel: +39  0554796.358    fax: +39 0554796.363
Dip. Sistemi  e  Informatica  Univ. di Firenze - via di S.Marta 3, 50139 FIRENZE  (Italy)

Home page: http://alanine.dsi.unifi.it/users/schoen
Global Optimization Laboratory (GOL): http://alanine.dsi.unifi.it/gol
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