As I said here : http://fusesource.com/forums/thread.jspa?threadID=2946&tstart=0, the ScriptEngine class (http://download.oracle.com/javase/6/docs/api/javax/script/ScriptEngine.html) provides a put method which enable to add a Java object into the created script, thanks to the JSR-223. But Camel does not provide a "bridge" to this method.
So I propose to pass the arguments via the header map of the message.
Indeed, on client side, I created a Map<String, Object> which contains the future scripts arguments. Then I put this map into the header.
Next on the camel-script component, I check a particular key (a public static final attribute that I added) and if the value returned is a Map, I try to add the Map's objects with the engine.put(String, Object) method.