Titular Bishop of San Leone
On the feast of the Epiphany, Pope Benedict XVI had announced that he created Mgr Prospero Grech OSA a cardinal and Titular Archbishop of San Leone in Calabria, Italy.
I guess that before Pope John XXIII, not all cardinals were consecrated bishops.
Cardinals are divided into three sections, namely: cardinal bishops, cardinal priests and cardinal deacons.
Only cardinal bishops were consecrated bishops but Pope John XXIII decreed that all cardinals be consecrated bishops.
Though they enjoyed all pontifical rights in ceremonies, cardinals in the other two sections were not consecrated as bishops.
Now, since Mgr Charles Scicluna was appointed by Pope Benedict XVI as Auxiliary Bishop of Malta he was entitled to be named Titular Bishop of San Leone. The same title was already given to Cardinal Grech.
I do not know whether another titular see was given to Cardinal Grech.
The diocese of San Leone in Calabria was founded in 1322 and was suppressed in 1818. It was restored as a titular Episcopal see in 1968.