encodeURIComponent doesn't follow rfc3986 that oauth requires. This is my fix...

oauthPercentDecode

var oauthPercentEncode = (function(){

  var escapeChars = "!*'();:@&=+$,/?%#[]",
      matchChars  = new RegExp( "([\\" + ( escapeChars.split('').join('\\')) + "])", "gi");

  return function( p ) {
    return p.replace( matchChars, function( char ) {
      return '%' + ( "" + char ).charCodeAt(0).toString(16).toUpperCase();
    })
  }

})();