http://bugs.winehq.org/show_bug.cgi?id=21394
--- Comment #1 from Hin-Tak Leung htl10@users.sourceforge.net 2010-01-16 17:25:40 --- Apparently the non-functioning of the "+" syntax is a known issue: see programs/cmd/builtins.c, line 166 FIXME: Add support for a+b+c type syntax
And there is no special treatment for device files like null.