Yes. Using the jmx-console, look up the jboss.system:service=MainDeployer mbean, and then use the deploy method that takes a string as a parameter, passing the full path name to the ear/war/whatever file. Note that the file as named must be visible to the server. You could also use twiddle to accomplish the same thing. Note that if you restart the server you will have to redeploy the application.
Personally, I simply stop the server, copy my app to the deploy directory, and restart the server. Only takes a minute on my system, and avoids curious redeployment issues that tend to crop up every now and then. Scripting this in Ant is easy.