Heard the same happened to an Airtours aircraft over France about a week after the New York atrocity.
Missed his call sign a few times and bingo, fighter on your wing.
I think the Kestrel R/T call was, “could you ask the fighter to turn his transponder off” playing havoc with his TCAS no doubt.
Reply from ATC “negative Kestrel, you will be escorted to the on your route to the FIR boundary”.
No further incident was reported.