note this was supposed to be a comment, and It doesn't answer not answer the question directly. It questions the usefulness of the question.
Quit using emma and start using jacoco. AFAIK, emma has been dormant since around 2007. The latest version of the emma plugin on maven central is from 2010.
As of today (fist quarter 2013). There is a version on maven central from feb-2013.
<dependency>
<groupId>org.jacoco</groupId>
<artifactId>jacoco</artifactId>
<version>0.6.2.201302030002</version>
</dependency>
And it is synchronized with the maven plugin. Here is an example of a configuration of mine
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>**/entities/*</exclude>
</excludes>
</configuration>
<executions>
<execution>
<goals>
<goal>prepare-agent</goal>
</goals>
</execution>
<execution>
<id>report</id>
<phase>prepare-package</phase>
<goals>
<goal>report</goal>
</goals>
</execution>
</executions>
</plugin>
The reports from jacoco also look nicer than the ones in emma.
Compare:
with