function disableclick(e) {
  if (document.all) {
  if (event.button==2||event.button==3) {
  if (event.srcElement.tagName=="IMG"){
   document.oncontextmenu=function(e){return   false;}   
  return false;
  }else{
   document.oncontextmenu=function(e){return   true;}   
  }
  }
  }
  else if (document.layers) {
  if (e.which == 3) {
   document.oncontextmenu=function(e){return   false;}   
  return false;
  }else{
   document.oncontextmenu=function(e){return   true;}   
  }
  }
  else if (document.getElementById){
  if (e.which==3&&e.target.tagName=="IMG"){
   document.oncontextmenu=function(e){return   false;}   
  return false
  }else{
   document.oncontextmenu=function(e){return   true;}   
	  }
  }
  } 
function associateimages(){
  for(i=0;i<document.images.length;i++)
  document.images[i].onmousedown=disableclick;
  } 
if (document.all||document.getElementById)
  document.onmousedown=disableclick
  else if (document.layers)
  associateimages()