Umlauf and Burchard (2003) present a generic length-scale equation... for use in two-equation models of turbulence. However, because of the traditional form used for the diffusion term, it can be used at present for only negative values of n. We show that a simple modification of the diffusion term is sufficient to insure a more universal generic length-scale equation that is valid for all values of m and n, including positive values of n. We also show that an appropriate combination of exponents m and n will enable the generic length-scale equation to simulate any desired length-scale equation...