This problem still exists for me. At random, after restaring KDE/system,
sometimes kwalletmanager starts with empty window (doesnt who any wallets in it)
and when I dragdrop .kwl files to that window, then manager puts them into
directory
/home/rafal/.kde/share/apps/kwallet
yet they are still
w.r.t. the silent failure - this seemed noteworthy since in my
experience KDE is quite happy to pop up dialog boxes to tell you that
there was an error communicating with klauncher, or artsd failed to open
a sound device, or a protocol (e.g. http) handler process has died
unexpectedly.
--
Wallet