Pdf is possible with jqgrid?, if is not, what another library do you suggested me for do reports?

I do the following,

  jQuery("#req_p").jqGrid('navButtonAdd','#req_p1',
     {caption:"Imprimir",
      buttonicon:"ui-icon-print",
      onClickButton:function(){
       imprime();
      },
      position:"last",
      title:"Imprimir",
      cursor: "pointer"});

then in "imprime",

 function imprime(){
  ajax=nuevoAjax();
       ajax.open("GET", "rep_solic_almac.php", true);
       ajax.onreadystatechange=function(){
        if (ajax.readyState==4){
         var respuesta=ajax.responseText;
         if (respuesta=="OK"){
          alert(respuesta);
         }
        }
       }
       ajax.send(null);
 }

I just sent, "rep_solic_almac.php", and it doesn't work, what I expected, is that a page PDF opened, could anybody help me?

Sorry for my English

Thank you in advanced