As of now (v9.3 of postgreSQL), you need to rebuild old (lost) master from new master.
Glad you could discover the magic of pgpool :-)
You can either use pgpoll admin to do this rebuilding in a single click or you can write your own shell script (like I had done) to resotre a lost node (do remember to test a scenario where slave is lost and you have to rebuild that).
Regards
Sameer
PS: Sent from my Mobile device. Pls ignore typo n abb