function showHideImage(){
  if($('categoryImg').getHeight() <= 35) {
    new Effect.Morph('categoryImg', {style: "height:210px;",
    				     afterFinish: function(){
    $('imgSpacer').setStyle({"backgroundImage":"url('fileadmin/templates/main/images/imgUp.png')"});
    				     }});
  }
  else {
    new Effect.Morph('categoryImg', {style: "height:0px;",
    				     afterFinish: function(){
    $('imgSpacer').setStyle({"backgroundImage":"url('fileadmin/templates/main/images/imgDown.png')"});
    				     }});
  }  
  
}