I have seen an IR flight listed today on TUN website arriving from and departing to Tehran, and i see it now on http://fr24.com/IRA3475. It's a bit delayed but who cares :-P
The return is IR/IRA3474. The flight will be serviced out of TUN's Terminal 2.
Anyone here knows the purpose of flight ? I doubt it's diplomatic as it won't depart the same night in that case !