Javascript String valiDate()

/*/*  w w w .  j  ava  2  s  .  c  o  m*/
 * valiDate
 * http://www.karalamalar.net/
 *
 * Copyright (c) 2009 Izzet Emre Erkan
 * Licensed under Creative Commons Attribution-Share Alike 3.0 Unported License
 * http://creativecommons.org/licenses/by-sa/3.0/
 *
 */
String.prototype.valiDate =
  function () {
    if (/^(0[1-9]|[12][0-9]|3[01])[- /.](0[1-9]|1[012])[- /.](19|20)[0-9]{2}$/.test(this)) {
      var v = this.replace(/[- /]/g, '.').split('.'),
        d = parseInt(v[0], 10),
        m = parseInt(v[1], 10),
        y = parseInt(v[2], 10),
        o = new Date(y, m - 1, d);
      return o.getDate() === d && o.getMonth() + 1 === m && o.getFullYear() === y ? o : false;
    } else {
      return false;
    }
  };