Some tips ...
Your XML context files should be in the ${jetty.base}/webapps/ directory.
(It appears you are still on the old-school method of modifying ${jetty.home}, might want to read up on the
jetty.home vs jetty.base split, it will make your life easier in the long run)
There were some fundamental behavioral nuances in the split between /contexts/ and /webapps/ that confused many people, and resulted in duplicate deployments of the same webapp in an overwhelming number of cases, the 2 separate directories were merged together with some basic basename logic to minimize the dual deployment issues that many had.
The XML file format has changed slightly (mainly just a new DTD reference that *must* be updated), be sure you update your XML files.
If you have your *.war (or webapp directory) in the ${jetty.base}/webapps/ directory too, then make sure your XML file and the basename of the webapp is the same (otherwise you'll have double deployment).
Said another way...
if you have in ${jetty.base}/webapps/
search.war <-- this is ignored, because search.xml exists)
search.xml <-- this is used
admin.xml <-- this is used
webadmin.war <-- this is deployed as the /webadmin context path (even if admin.xml references it)
mystatic/ <-- no WEB-INF/web.xml in here? then its a deployment of static content to the "/mystatic" context path
Note: if you are using xml deployment descriptors, then you don't need to have the war file in ${jetty.base}/webapps/ too.
To see what was actually deployed, set "jetty.dump.start=true" in your ${jetty.base}/start.ini and check your logging output, it will include the server state tree (including all handlers + webapps).