I've checked my books, google, API... I don't get it. A redirect_to doesn't really start a wholly new request. Code after a redirect_to still gets processed. The original request code isn't terminated.
A) what's the sense in that?
B) how prevent it?
Example code causing me problem is below...
# processing continues here even if
# check_session_not_expired invokes the redirect_to
if (params[:controller] != 'login') &&
(!@current_user.login_is_valid? || !self.session_valid?)
flash[:session_expired] = true
redirect_to(:controller => :login, :action => :login)
# do stuff
# return true or false