Fails on @software in bibtex file.

[VorpalBlade]

WARNING: Caught exception "AttributeError: 'Style' object has no attribute 'format_software'". Reloading.

This happens when trying to cite:

@software{guennebaudEigenV32010,
  title = {Eigen V3},
  url = {http://eigen.tuxfamily.org},
  date = {2010},
  author = {Guennebaud, Ga\"el and Jacob, Beno\^it and others}
}

Presumably this would have to be added to the style class. I could certainly write some code for it, but I have no idea how you would prefer to format such citations in the style you have included.

Citing this using normal LaTeX works fine with biber at least (haven't tried bibtex/bibtex8) using the numeric IEEE style.