Using units package with custom options

[martin]

Hi,

Want to disable default in book class

\usepackage{units}

so I can use 

\usepackage[ugly]{units}

because I'm getting


        The package units has already been loaded with options:
        []
        There has now been an attempt to load it with options
        [ugly]
        Adding the global options:
        ,ugly
        to your \documentclass declaration may fix this.
        Try typing <return> to proceed.



Thanks 

Martin