Custom date format in stream

I just installed Beta 1 and noticed that I am no longer able to influence the format of the date display in the activitystream block.

With RC2 I this date followed the "medium" date setting which allowed me to set a French date format. The imposed format in Beta2 looks awkward as in French the day always comes before the month (e.g. 22 novembre, not novembre 22).

Indeed in beta1 I found this:

function theme_activitystream_header($action) {
  return '<h3 class="datehead">' . format_date($action->created, 'custom', 'F j, Y') . '</h3>';
}

which replaces this from RC2:

function theme_activitystream_header(&$action) {
  return '<h3 class="datehead">' . format_date($action->created, 'medium') . '</h3>';
}

Would you have an objection to going back to the RC2 implementation?

Thanks,

~/jc