http://bugs.winehq.org/show_bug.cgi?id=30436
--- Comment #9 from Dan Kegel dank@kegel.com 2012-10-24 22:28:10 CDT --- I've got wine-1.4, not sure that was ever outfitted with new gecko. Removing ~/.wine and rerunning, then checking date on a file shows:
-rw-rw-r-- 1 dank dank 3248654 Nov 9 2011 /home/dank/.wine/drive_c/windows/system32/gecko/1.4/wine_gecko/mozjs.dll
which predates the bug report.