I imagine the encoding should work regardless of the GET/POST method (depending on what your're trying to do) but if you are not familiar with the characteristics and differences between the two, I seem to remember Ovid posting some good info in response to POST vs GET & their intermingling.

Also, in Perl Cookbook in chapter 19: CGI Programming, they have an excellent discussion on the topic.

@a=split??,'just lose the ego and get involved!';
for(split??,'afqtw{|~'){print $a[ord($_)-97]}