Hi,
My experiences are that you can't suppress this message using script. Acrobat probably considers it a security issue and expects the user to acknowledge / allow the database connection (at least once). There is a "remember my choice" tickbox, which when ticked should prevent the user seeing the message again.
I know that the message keeps coming up when previewing within LC Designer, but it should remember the user's choice when opened in Acrobat/Reader.
Someone lese may have a better explanation or workaround.
Good luck,
Niall