add selenium extension

[anutron]

Is it possible to add an extension to Play's implementation? Looking
at the docs on user exensions (http://seleniumhq.org/docs/
08_user_extensions.html) you put them in a js file and invoke selenium
with a reference to it, but that's not going to work so well for play.
Suggestions?

BTW, I'm doing this as a workaround for the fact that
selenium.browserbot.getCurrentWindow().foo is always undefined; you
can't reference global variables at all (in play 1.2.3), so I've got
this crazy workaround to give me access to the global environment and
I want to turn this into a selenium action rather than the long string
of Javascript in my tests...