It was created for the movie. As far as I know it has no real historical connotation.
The translation is: “Serpent’s breath, charm of death and life, thy omen of making.” from http://dandalf.com/charm.html Really its an interesting look at the origins of the language the filmmaker used.
Ah... I love that movie, I am gonna have to go dig it out of the CD archive (cardboard box in garage LOL).
"Oh, you do know something of the Art. Do you have the Sight? Do you see the future?" (Excalibur Script)