if (navigator.userAgent.indexOf("MSIE 3") == -1)
{
   if(top.frames.length == 0 )
   {
      document.write('<frameset rows="120,*">');
      document.write('<frame name="boven" src="titel.html" scrolling="no"  noresize frameborder="0" title="Frame boven: titel">');
		document.write('<frameset cols="120,*">');
		document.write('<frame name="links" src="nav.php" scrolling="auto" resize frameborder="0" title="Frame links: navigatie">');
      document.write('<frame name="midden" src="')
		document.write(self.document.location)
		document.write('" scrolling="auto"  resize frameborder="0" title="Frame midden: hoofdframe">');
      document.write('</frameset>');
      document.write('<\/frameset>');
		document.write('<\/html>');
      top.frames[2].location.href=self.document.location;
   }
   else
   {
     if(top.frames.length != 0 &&
       (top.frames.length !=3 || (top.frames[2].name != "midden"))) 
     {
        top.location.href = self.document.location;  
     }
   }
}