The project is located here.
Example setup (works well with my projects) looks like:
<plugin>
<groupId>org.riedelcastro</groupId>
<artifactId>maven-gcupload-plugin</artifactId>
<version>1.0</version>
<configuration>
<uploads>
<upload>
<extensions>jar</extensions>
<labels>Featured,Type-Archive,OpSys-All</labels>
</upload>
<upload>
<extensions>jar</extensions>
<postfix>sources</postfix>
<labels>Featured,Type-Source,OpSys-All</labels>
</upload>
<upload>
<extensions>jar</extensions>
<postfix>javadoc</postfix>
<labels>Featured,Type-Docs,OpSys-All</labels>
</upload>
</uploads>
</configuration>
</plugin>
The gcupload:gcupload maven target is added to our Hudson. We have differentia-javaica release build which takes care of everything - deploying jars to our Nexus as well as putting them to Google Code.