Doubt regarding quoted-pair

If a header (say, Content-Disposition) contains a quoted-string that
includes a quoted-pair,
how should the quoted-pair sequence be treated - if the character
following the backslash is
NOT a "special" character.

Example:  Given the string "C:\dir\file.txt", within a
Content-Disposition header, if I use the
RFC822 parsing rules, I'll end up with "C:dirfile.txt", since as per
RFC822 (actually from:
the rfc822 update - draft-ietf-drums-msg-fmt):

3.2.2 Quoted characters

Some characters are reserved for special interpretation, such as
delimiting
lexical tokens. To permit use of these characters as uninterpreted data,
a
quoting mechanism is provided.

quoted-pair     =       ("\" text) / obs-qp

Where any quoted-pair appears, it should be interpreted as the text
character alone.
--------
I think in this case, the string should be :C:\\dir\\file.txt

I don't see anything in RFC 2068 regarding this, leaving this case
ambiguos - I think.

Comments ? (I'm not in this mailing list, so include my email address as
well)

-john