Weirdness with Emacs' X window id

[Peter Heslin]

In Debian GNU/Linux:

If I do emacs -q --no-site-file with a month-old CVS checkout, and
then M-x eshell:

~ $ xdpyinfo |grep -i focus
focus:  window 0x1400015, revert to Parent
~ $ wmctrl -l |grep -i emacs
0x01400014 1 aideen Emacs *eshell*

where wmctrl is a command-line program and the -l switch makes it list
all current windows.  Note that xdpyinfo and wmctrl disagree as to
what should be the ID number for the single Emacs frame.  One says a
number ending in 14, the other in 15.

wmctrl -l does not know of any window with the ID 0x1400015.

Is this expected?  I don't know anything about these IDs -- I'm just
trying to write a script to manipulate windows on my desktop, and
it's quite difficult with this ID schizophrenia.

Emacs is the only application I run that behaves like this.

If it's not expected behavior, then it could be a bug in wmctrl,
xdpyinfo, my X server, Emacs, or who knows where, so it would be
interesting to see if anyone else sees this.

Peter