Check Connection on iPhone

I'm trying to check my iPhone-app for internet connection, I always get this error message:

* +[Connection isConnected]: unrecognized selector sent to class 0x3bcd500

* Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** +[Connection isConnected]: unrecognized selector 开发者_运维知识库sent to class 0x3bcd500'

I use this example: http://www.xprogress.com/post-40-iphone-internet-connection-check-wifi-3g-edge-something-like-reachability-h/

Can someone help me and assist me to figure out what I'm doing wrong?

Thanks, Alex.

Have you added Connection.m into your project?

Don't you get a warning that Connection is undefined or may not respond to selector when compiling?