AJax working in IE but problem in mozilla

[balaganesh.k89]

this java script ajax function working well in IE.. but prblem in Mozilla

 

the mma function always starting first ...

 

 

<script language="javascript">

function getHTTPObject()

  {

if (window.ActiveXObject) return new ActiveXObject("Microsoft.XMLHTTP");

else if (window.XMLHttpRequest) return new XMLHttpRequest();

else

{

alert("Your browser does not support AJAX.");

return null;

}

  }

 

 

 

  function hsc(va2)

  {

 

  var zs,zs1,y1,y2,zz,z1,y3;

  zs=va2;

 

      y1=document.getElementById(zs).src;

      y2=y1.match("minus_symbol.gif");

  y3=y1.match("plus_symbol.gif");

      zs1= zs.split("img");

zz=zs1[1];

    if(y2=="minus_symbol.gif")

    {

z1='ct='+zz;

  b="img"+zz;

    url ="get_catname.php";

objXMLHTTP1 = getHTTPObject();

    objXMLHTTP1.open("POST",url,true);

objXMLHTTP1.onreadystatechange = stateChanged;

    objXMLHTTP1.setRequestHeader('content-type','application/x-www-form-urlencoded');

objXMLHTTP1.send(z1);

       

            function stateChanged()

                {

                      if (objXMLHTTP1.readyState==4)

{

  document.getElementById(zz).innerHTML="";

                              document.getElementById(zz).innerHTML=objXMLHTTP1.responseText;

  document.getElementById(b).src="images/plus_symbol.gif";

}

                } 

      }

    if(y3=="plus_symbol.gif")

  {

   

              mma();     

      }

 

  function mma()

  {

 

    b="img"+zz;

z='ct='+zz;

 

    url ="get_subcategname.php";

objXMLHTTP = getHTTPObject();

    objXMLHTTP.open("POST",url,true);

objXMLHTTP.onreadystatechange = stateChanged;

    objXMLHTTP.setRequestHeader('content-type','application/x-www-form-urlencoded');

objXMLHTTP.send(z);

       

            function stateChanged()

                {

                      if (objXMLHTTP.readyState==4)

{

                              m=document.getElementById(zz).innerHTML;

  document.getElementById(zz).innerHTML=m+objXMLHTTP.responseText;

  document.getElementById(b).src="images/minus_symbol.gif";

 

}

                  }   

    }