[jQuery] Trouble with extending Object prototype

[Bill]

Hi all,

I extended the Object object with a method called getKeys() that works
like Perl's keys() function -- given a hash, or associative array, the
method returns an array containing all keys:

Object.prototype.getKeys = function() {
        var arr = new Array();
        for (var s in this) {
                if (this.hasOwnProperty(s)) arr.push(s);
        }
        return arr;
}

However, when I include this function definition anywhere in a page,
jQuery reports the following error:

name.replace is not a function
name = name.replace(/-([a-z])/ig, function(all, letter)
{            jquery-1.2.6.js (line 1115)

Any idea why this might be happening?

Thank you kindly,

--Bill