Well, outside of .hack an Epitaph is the name given to the carvings on a tombstone. Which makes it a rather fitting name for something written by a dead woman. It is possible that the Epitaph is carved into the cell phone, but it's hard to tell. Personally, I've always seen it as representing Morganna. A sort of physical avatar for a being that has no physical body if you will.
Or maybe Morganna just got lonely and started texting Tsukasa.
Anyway wasn't the name given to that item Tsukasa got the "Tablet of Twilight"? Similar to know Kite got the "Book of Twilight"? That's what I've always called it.
Do you think that is the film script? And if so, maybe someone who can read it could skim through it and find out what they call the object that Tsukasa finds in that chest.
What's bugging me is I saw a CRtwenty on that forum as well. =) I think he's on multiple .hack forums and such, which is why he seems so well informed in it.
As for the filmscript, I'd like to know the given name of the object as well. But it would suck if they actually called it <unnamed object> or something like <rock>.