Tests are not executed (nether coverage) when configuring a maven 2 build and specifying MAVEN_OPTS on multiple lines like this :

-XX:MaxPermSize=512m
-Xms128m
-Xmx512m

With an mvn help:effective-pom, I can see the following, which probably disturb maven (with no complain) :

<plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.4.1</version>
          <configuration>
            <argLine>-XX:MaxPermSize=512m
-Xms128m
-Xmx512m</argLine>
[...]
</plugin>

If I put all options on the same line, tests are well executed. It should be good to remove new line when passing to Maven.