Trying to make my way on the examples of 'Open Source ESB's In Action' by Manning (nice book by the way). The book is using Mule and Apache Service Mix. When it comes to Mule, version 2.2.x is the reference one. Eventually if you are a MacOSX user running Java2 version 6 (64bit), you wont be able to run any of the examples due to several incompatible (native) library problems.
Luckily there is a quick fix and you may find it here (original workaround based on a post here). Make sure you have properly set your MULE_HOME env variable and you have the appropriate version of mule + the wrapper, the proposed shell script will do the rest.
The work is based on a Tanuki's software, Java Service Wrapper - in case you are wondering.
By the way if you have just bought the book and downloaded the source/ examples before issuing the initial ant command that will download and set the example's environment make sure to edit the /enviroment/prepareResources/prepare.properties file and modify the value of instal.target property. Initially it seems that the script thinks your system as a Windows machine and creates weird "c\" like folder names! I just used a ./myFolderTests value.