var currentEditorText = "";

function addEditorBehavior(){
     Event.observe('text', 'change', function() {
       changeEditorText();
     });
     Event.observe('editorForm', 'submit', function() {
       saveEditorText();
     });
}
function changeEditorText(){
     saveEditorText();
     if( $('text').value == "" ){
          tinyMCE.setContent('');
     } else {
          tinyMCE.setContent(unescape($($('text').value).value));
          currentEditorText = $('text').value;
     }
}
function saveEditorText(){
     if( currentEditorText != "" )
          $(currentEditorText).value = escape( tinyMCE.getContent() );     
}

addLoadEvent(addEditorBehavior);