--no-name-remapping
Allow Common Name, X509 Subject, and username strings to include any printable character including space, but excluding control characters such as tab, newline, and carriage-return.
By default, OpenVPN will remap any character other than alphanumeric, underbar ('_'), dash ('-'), dot ('.'), and slash ('/') to underbar ('_'). The X509 Subject string as returned by the tls_id environmental variable, can additionally contain colon (':') or equal ('=').
I think equal and colon is remapped anyway.
