Today I tried to build a dynamic endpoint URL for one of my camel routes. I am using the Spring properties bridge to load configuration parameters and I try to build the endpoint URL using my configuration and request headers. This is what my recipientList looks like: restlet:?parameter=$simple{in.header.myHeader} The important part is the $simple{in.header.accessToken}. First I was using the usual Camel syntax ${in.header.accessToken}, but always got an exception on startup stating