Mercurial 1.1: hg clone & update leave files modified

[TK Soh]

I have noticed this a few times now. Somehow with Mercurial 1.1, hg
clone & update (from null) can sometimes leaves some files modified in
the repos. And strangely, hg diff is unable to see any modifications.
I only tried this on Windows (XP, SP2):

    C:\repos>hg clone hg hg-progress
    updating working directory
    947 files updated, 0 files merged, 0 files removed, 0 files unresolved

    C:\repos>cd hg-progress

    C:\repos\hg-progress>hg tip
    changeset:   7463:6aafd75fb924
    tag:         tip
    user:        Matt Mackall <mpm at selenic.com>
    date:        Tue Dec 02 13:06:18 2008 -0600
    summary:     Added signature for changeset 2a67430f92f1

    C:\repos\hg-progress>hg status -mard
    M hgext\keyword.py
    M tests\test-mq-qclone-http

    C:\repos\hg-progress>hg diff ---git

    C:\repos\hg-progress>hg verify
    checking changesets
    checking manifests
    crosschecking files in changesets and manifests
    checking files
    1107 files, 7464 changesets, 14641 total revisions

    C:\repos\hg-progress>hg version
    Mercurial Distributed SCM (version 1.1)

    Copyright (C) 2005-2008 Matt Mackall <mpm at selenic.com> and others
    This is free software; see the source for copying conditions. There is NO
    warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

    C:\repos\hg-progress>hg debugfsinfo
    exec: no
    symlink: no
    case-sensitive: no