use shared+folder at domain.tld to put mail directly in a subfolder of a shared folder ?

[Matthias Busch]

currently it does not seem to work

Apr  1 13:29:58 kolab postfix/error[17302]: A0907B00F43: 
to=<shared+shared/info at domain.tld+spam>, orig_to=<info+spam at domain.tld>, 
relay=none, delay=4573, delays=4573/0.02/0/0.01, dsn=4.1.3, 
status=SOFTBOUNCE (bad address syntax)

does anyone know how I we might get this to work?

thanks
Mat