Use a field as a button and make it run a script. Then you can change the text to whatever you want.
To expand on that, you can place a text field on top of a layout button object set up to "do nothing". Then group the field and button object, setting it up as a button to perform the desired script. Then your script, as posted already, can modify the contents of the text field to change the button's name.
thanks for the idea!