reading anharmonic VSCF spectra

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Hello all,
I'm trying to work with anharmonic spectra calculated by the nwchem, however, opening ecce.out I'm getting only the harmonic approximation. Do you have any idea if it is possible to get anharmonic corrections into ecce as well? If not, do you have any suggestions for a program that can read nwchem output and work with them?
I have tried also Avogadro (also version 2), but I get "could not read file" error, and Chemcraft - which recognizes only the harmonic approximation as well.
I would be grateful for any suggestions (in the longer term scale also for suggestions how to build my own code/extend the existing ones if nothing is available).
Thank you.

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Extending code: see the apps/scripts/parsers directory which has parser scripts in perl. See e.g. gaussian-03.vib and nwchem.vib for the code that reads in frequencies.

Can you provide a short model job generating anharmonic spectral data that one could try?

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Sorry, I didn't see notification and then forgot about the post because of christmas... thank you for the tip, i'll check the scripts. here is the example (I ran with pair coupling with 16 grid points and it took few hours, here is diagonal coupling with only 8 grid points so it should be pretty fast):
start h2o

title "h2o anharmonic spectra"

geometry units angstroms print xyz autosym
  O       -1.50896        1.31694        0.00000
  H       -0.53896        1.31694        0.00000
  H       -1.83229        1.94831       -0.66162

 * library 6-31+G*

 xc b3lyp
 CONVERGENCE density 1e-8
 CONVERGENCE energy 1e-7
 GRID lebedev 99 14 ssf euler

 dielec 2.24

 EPREC 1e-7
 GRMS 0.000004

 ngrid 8
 coupling diagonal

ECCE_PRINT h2o.ecce.out

task dft optimize
task dft vscf

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