For people trying to connect with iMessage but you get a rply saying 'please check you're network connection and try again later', I got a solution to it and it really works! (:
Just go to 'settings' and then 'wifi' and click at the blue arrow of whatever connection you're useing, just type 8.8.8.8, 8.8.4.4 for the colum that says DSN and then login with you're apple ID on iMessage! :D and do like this and comment, if it works for you too! :) thank you!
iPad, iOS 5