Subprocess : Editor for Called Elements should allow to sort list of processes

When taking a reusable subprocess onto canvas and opening its properties selecting the list of candidate processes in Called Element field, I get the list of validated processes contained in my Guvnor repository but in "random" order.
I would like to sort the list on Process Id, as I have 163 items listed.
Sort options are greyed-out in columns header.
Can you helpme please ?
Kind regards, David.