You can simply reuse the message form by creating the buttons you will need for it and then coding the On-Click event to perform different functions based on a hidden text field. When you call the message form, you will need to specify the information you need. For example, let's say you need a message box with a button to close the message form after the user reads it ( a simple Close button). The button's name is cmdButton1.
In the form calling the message box, you would first code it to open the message form and then:
With forms!MESSAGEFORMNAME
.cmdButton1.caption = "Close"
.HIDDENTEXTBOX = "Close"
End With
Then under the code for the Close Button, you would use a Select Case statement to tell it what to do.
Select Case HIDDENTEXTBOX
Case "Close"
docmd.close
exit sub
Case "Something Else"
do something else
End Select
This way, the button will perform different tasks depending upon the value that you set the hidden text box to .
HTH