function isAlphaNumeric(YourAlphaNumeric){ 	

	resultado=true;
		if(/^[a-z0-9 A-Z'*?"+,\u0024\u0025\u002F\u0025\u0024\u00e1\u00e9\u00ed\u00f3\u00fa\u00c1\u00c9\u00cd\u00d3\u00da\u00f1\u00f1]+$/i.test(YourAlphaNumeric)) {
			resultado=true;
		}		
			else {
				resultado=false;
			
			}
	
	return resultado;
}

function validarCadena(cadena){
  if(cadena){
      var arrayTokens = cadena.split(" ");
      
      var arrayString = new Array();
      if( arrayTokens.length == 1 && arrayTokens[0] == '*' ){
          return arrayTokens[0];
      }
      for( var i = 0, j = 0; i < arrayTokens.length ; i++ ){
          if( arrayTokens[i].length != 0 ){
              if( isAlphaNumeric(arrayTokens[i]) ){
                  arrayString[j] = arrayTokens[i];
                  j++;
              }
              else{
                  return null;
              }
          }
      }
      if(arrayString.length == 0 )
          return null;
      var cadenaNueva = arrayString[0];
      for(var x = 1; x < arrayString.length ; x++){		
          cadenaNueva += " " + arrayString[x];
      }
      return cadenaNueva;
  }
  return null;
}