Why can't I /address@hidden:/ with tramp?

[Harry Putnam]

Using:
GNU Emacs 24.0.92.1 (i686-pc-linux-gnu, X toolkit) of 2012-01-13
Tramp: 2.2.5-pre

If I try to use emacs to access a directory on nearby windows boxes
with:

C-x d <RET> /address@hidden:/ <RET>

It does ask for password and then just hangs there.

This has been a problem here for quite some time, but I thought maybe
the latest versions would act differently.

Here is a back trace from C-g after 

/address@hidden:/ <RET>
Password: XXXXXXX <RET>

(Here the little timer bar starts spinning)

C-g <RET>

Debugger entered--Lisp error: (quit)
  signal(quit nil)
  byte-code("\302!\210\303     @       A\"\207" [vec err tramp-cleanup signal] 
3)

[ ... ] Byte code snipped

  tramp-maybe-open-connection(["ssh" "harry" "m2" "" nil])
  tramp-send-command(["ssh" "harry" "m2" "" nil] "cd ~; pwd")
  tramp-sh-handle-expand-file-name("/address@hidden:" nil)
  apply(tramp-sh-handle-expand-file-name ("/address@hidden:" nil))
  tramp-sh-file-name-handler(expand-file-name "/address@hidden:" nil)
  apply(tramp-sh-file-name-handler expand-file-name ("/address@hidden:" nil))

[ ... ] byte code snipped

  tramp-file-name-handler(expand-file-name "/address@hidden:" nil)
  expand-file-name("/address@hidden:" nil)
  apply(expand-file-name ("/address@hidden:" nil))
  tramp-completion-run-real-handler(expand-file-name ("/address@hidden:" nil))
  tramp-completion-file-name-handler(expand-file-name "/address@hidden:" nil)
  expand-file-name("/address@hidden:")
  dired-noselect("/address@hidden:" nil)
  dired("/address@hidden:" nil)
  call-interactively(dired nil nil)

-------        ---------       ---=---       ---------      --------

Full backtrace attached:

backtrace.txt
Description: Text document