The RadEditor for MOSS 2007 version 4.5.3.0 has a Bug, which is very annoying...

You create a new custom tool in the ToolsFile.xml and set the “showtext” property.

<tool name="CustomToolName" showtext="true" /> 

Then you create a corresponding javascript method in the RadEditorCommandList.

RadEditorCommandList["CustomToolName"] = function(commandName, editr, oTool)
{
  (...)
}

If you now click on this new Tool Button, the RadEditor shows the message “Could not find the command xxx. Please update your command list.”

The solution for that: Remove the “showtext” property from your tool in the ToolsFile.xml and everything is working as expected.