I'm trying to create a custom URL scheme following the instructions here http://www.cocoadev.com/index.pl?HowToRegisterURLHandler and in the Cocoa Scripting Guide p108. I've not been getting anywhere! I've got at least two problems here: (I'm running OS X 10.6.6 with MacRuby 0.8) # Attempt #1 # AppDelegate.rb # experimental framework 'Foundation' framework 'ApplicationServices' class AppDelegate def initialize registerExperimental end def registerExperimental sharedAEManager = NSAppleEventManager.sharedAppleEventManager sharedAEManager.setEventHandler(self, andSelector:getURL, forEventClass:kInternetEventClass, andEventID:kAEGetURL) end def getURL end end The above results produce an error - undefined local variable or method `kInternetEventClass' despite the fact that they are defined in HIServices/ InternetConfig.h. Is this where I need to delve into the depths of BridgeSupport? If the above is changed to def getURL(event, returnEvent) # do something with event here to parse the url end then I get wrong number of arguments (0 for 2) (ArgumentError) which is what I expected, but I am confused as to how to parse the 'andSelector' part of the code and sharedAEManager.setEventHandler(self, andSelector:getURL(event, withReplyEvent:returnEvent), forEventClass:kInternetEventClass, andEventID:kAEGetURL) is clearly wrong. Any guidance as to how to fix these two issues will be most gratefully received! thanks