MIXING POST AND URL PARAMETERS

       $color = $query->url_param('color');

    It is possible for a script to receive CGI parameters in the URL a
+s well
    as in the fill-out form by creating a form that POSTs to a URL
    containing a query string (a "?" mark followed by arguments). The
    param() method will always return the contents of the POSTed fill-
+out
    form, ignoring the URL's query string. To retrieve URL parameters,
+ call
    the url_param() method. Use it in the same way as param(). The mai
+n
    difference is that it allows you to read the parameters, but not s
+et
    them.

    Under no circumstances will the contents of the URL query string
    interfere with similarly-named CGI parameters in POSTed forms. If 
+you
    try to mix a URL query string with a form submitted with the GET m
+ethod,
    the results will not be what you expect.
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-- Randal L. Schwartz, Perl hacker