How to generate separate jar files for application, source, and documentation (for central.sonatype.org)

Sonatype has a repository that I want to deploy a jar file to, and they ask for separate files for application, sources, and javadocs:

Example:

example-application-1.4.7.pom
example-application-1.4.7.jar
example-application-1.4.7-sources.jar
example-application-1.4.7-javadoc.jar

In Scala SBT, I have a command called "package" that generates the jar file for the project, but that only generates "example-application-1.4.7.jar".

Question: What should I do to generate the other two jar files?