\'success message\' not displayed

Hello,
I have created a form that users can add information to (this is for people to RSVP their attendance at a function). In the "More Actions" tab (within the Form tab), I have selected the option to display a "success message" that says "Information Added Successfully". However, upon hitting the 'Submit' button, there is no such message displayed. Suggestions?
Thanks
Jeff
jemoore