fix proposal

// replace in .attr functions (there are two .attr functions)
        for (var key in params) {
            eve("raphael.attr." + key + "." + this.id, this, params[key]);
        }
// with
        var numericParams = {
            r:1,rx:1,ry:1,x:1,y:1,cx:1,cy:1,width:1,height:1
        };
        for (var key in params) {
            if (numericParams[key]) {
                params[key] = +params[key];
            }
            eve("raphael.attr." + key + "." + this.id, this, params[key]);
        }
// It's better make numericParams static somewhere