[Users] "Put deleted messages in . . . " ignored

[Graham P Davis]

Instead of dumping all my deleted messages in the same waste-bin, I
decided to configure my accounts to use their own trash-cans. To verify
that it worked, I set up a new trash folder and edited an account to
"put deleted messages in . . ." the new folder. Unfortunately, I
verified that it didn't work. Deleted messages still went in the
general trash and my new folder remained disappointingly empty.

Is there something I've missed in setting this up or does it just not
work?

-- 
Graham P Davis, Bracknell, Berks.
OS: Linux: openSUSE 13.2 (64-bit); KDE 4.14.2; Kernel: 3.16.6