socketstream and crc32

[Andrea Fontana]

I've compiled dmd 2.055 on ubuntu 64. It works fine but when I try to
use SocketStream dmd gives me this error:

/usr/include/d/dmd/phobos/std/stream.d(388): Error: module crc32 is in
file 'crc32.d' which cannot be read

My mistake?