Comment 18 for bug 676304

On xenial, I noticed that the Linux cifs client converts : to U+F022 (SFM_COLON) by default even when talking to a Samba with unix extensions. I think this happens in convert_to_sfm_char in linux's fs/cifs/cifs_unicode.c.

You can use the undocumented mount option "nomapposix" to turn off those character conversions, and then access to files with a colon works fine.