function doImg(obj_img){ //name_instance.extension
//---------------------------
	var obj_src_init = obj_img.src;
	if(obj_src_init.search('_off.')>0) obj_img.src = obj_src_init.replace('_off.','_on.');
	if(obj_src_init.search('_on.')>0) obj_img.src = obj_src_init.replace('_on.','_off.');
}

function doTree(code){
//--------------------------
var theForm = document.forms[0];
theForm.tree.value = code;	
theForm.submit();
}