If you are using Node action yes. Otherwise only make sure that your Javascript method is unique. Below an example how I Use it in my TaskScheduler package

 
/// <summary>
 
/// Create Javascript element that provides functionality to display the page
 
/// </summary>
 
/// <param name="Javascript"></param>
 
public override void RenderJS(ref StringBuilder Javascript)
{
 
base.RenderJS(ref Javascript);
Javascript.Append(
@"function openScheduleUrl(url){
parent.right.document.location.href = url;
}"
 
);
}
 
/// <summary>
 
/// Create Menu based on the Dropdowns.config xml file
 
/// </summary>
 
public override void Render(ref XmlTree tree)
{
 
//Render submenu
 
string executeOption = Enum.GetName(typeof(ExecuteOptions), int.Parse(NodeKey));
 
List<ScheduledTaskType> menuItems = DAL.ScheduledTask.GetSavedItemsForMenu(executeOption);
 
foreach (ScheduledTaskType menuItem in menuItems)
{
 
string icon = "../editor/calendar.gif";
 
XmlTreeNode node = XmlTreeNode.Create(this);
node.NodeID = menuItem.ScheduledTaskId.ToString();
node.NodeType = 
"ScheduledTasks";
node.Text = menuItem.Taskname;
node.Action = 
"javascript:openScheduleUrl('" + string.Format("{0}?scheduledtaskid={1}",UrlHelper.MakeUrlAbsolute("/plugins/TaskScheduler/Pages/ScheduleTask.aspx"), node.NodeID) + "');";
node.Icon = icon;
node.OpenIcon = icon;
tree.Add(node);
}
}