A simple way would be to create a text field with your rollover text, set to hidden.
this.getField("rolloverText").display = display.noPrint;
this.getField("rolloverText").display = display.hidden;
Hey Mark, thanks for your suggestion, I really appreciate it.
But how do you make a rollover button in Acrobat? And where do you go to format the text that will display in the rollover bubble/text box via the rollover link?