import java.util.zip.CRC32;
....
private void registerConcatenatedScript() {
	final CRC32 crc32 = new CRC32();
	final byte[] script = concatenatedScript.getContent();
	crc32.update(script);
	final long crc = crc32.getValue();
	application.addResource("/resources-" + crc + ".js", new ResourceLoader() {
		public InputStream getResourceAsStream(String resourceName) {
			return new ByteArrayInputStream(script);
		}
	});
	applicationContext.getStartupPage().addJsLibrary("rwt-resources/resources-" + crc + ".js");
}