Reproducibility issue with SODFT


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Just Got Here
6:17:40 AM PDT - Tue, May 6th 2014
Hello,

I am trying to run SODFT calculations on the iodine atom and they yield different electronic energies with the same input.
I first thought that the convengence criteria where too loose so I tightened them but with no succes.

here is my input file :
start i_with_SO
echo

charge 0

geometry
  zmatrix

     I

  end
end

basis "ao basis" spherical print
 I    S

        0.680300000      1.00000000

 I    S

        0.520800000      1.00000000

 I    S

        0.114300000      1.00000000

 I   S

        0.023792200      1.00000000

 I    P

        1.125000000      1.00000000

 I    P

        0.350800000      1.00000000

 I    P

        0.116600000      1.00000000

 I   P

        0.029974500      1.00000000

 I    D

        3.950200000      1.00000000

 I    D

        2.574200000      1.00000000

 I    D

        1.307100000      1.00000000

 I    D

        0.511600000      1.00000000

 I   D

        0.220000000      1.00000000

 I   D

        0.100000000      1.00000000

 I   F

        0.426500000      1.00000000

 I   F

        0.170000000      1.00000000
end

ecp
I library crenbl_ecp
end

so
 I P

       2        0.9111             -8.943754

       2        1.0658             23.698540

       2        1.3899            -24.499522

       2        1.7958              9.482398

       1        2.5479              1.858838

       0        1.1725             -0.172766

 I D

       2        0.8653             -0.236477

       2        0.8996              0.215437

       2        4.5872              0.734985

       2        5.5282             -0.401384

       1       22.2080             -0.567771

       0       19.1401              0.039591

 I F

       2        2.0066             -0.038072

       2        5.4120              0.130806

       2       20.8879             -0.245891

       1       63.8211              0.331683
end

dft
mult 2

xc m06-2x

 grid xfine

 convergence energy 1.000E-07

 convergence density 1.000E-06

 convergence gradient 1.000E-05

 iterations 200
end

task sodft energy

Here are examples of the energy I get with the number of iterations before if converges :
1) -111.256242105425 after 73 iterations
2) -111.261775078069 after 176 iterations
3) -111.261470628259 after 78 iterations
4) -111.261784696829 after 75 iterations

Has anyone encountered the same problem ?
Is there a way to avoid such an uncertainty or am I spotting a bug on nwchem program ?

Thanks in advance for your help.
Regards,