Michael Richards (Kramer) and Wayne Knight (Newman) had a wonderful chemistry on the set. In the episode The Reverse Peephole (season 9) they reverse the peephole in their door in order to prevent an ambush.
Kramer says he now will be able to peek in to see if anyone is waiting to jack him with a sock full of pennies. It doesn't concern Kramer and Newman that people will be able to see in:
Our policy is, we're comfortable with our bodies. You know, if someone wants to help themselves to an eyefull – we say, 'Enjoy the show.'
Season 9 will be released on DVD November 6.
Wikipedia on Michael Richards
Wikipedia on Wayne Knight
Find Seinfeld Season 9 at Amazon