weird interaction between save-interprogram-paste-before-kill & mouse-autoselect-window

[Sam Steingold]

after I updated emacs this morning, I observe the following ugliness:
emacs -q
q (remove splash screen)
C-x 2 (get two windows)
evaluate in *scratch*:
(setq save-interprogram-paste-before-kill t
      mouse-autoselect-window -0.1)
now, select a word in one window with a mouse1 double-click, let it be the word 
"first".
then select a word (say, "second") in the second window also with mouse1 double 
click.
now, move the mouse back to the first window and observe that the word "second" 
no longer looks selected, while the word "first" no looks selected.
now click mouse2 (inside the first window) - "first" is inserted in the first 
window, not "second" (which was the last word I selected with the mouse!