You will need to compile your own custom version I think…
There is a properties file that will allow you to control some of these things and lock stuff down.
Here’s two great guides on how to build your own custom spark:
http://community.igniterealtime.org/thread/48931 (skip to the Spark part, focuses on “branding” of spark, but you will be in the same properties files and stuff as the other settings, so just read the props file and you may find what you are looking for.)
You may have to “merge” the two guides as you go along, but for the most part it’s pretty easy once you figure it out.