Maven no encuentra pruebas JUnit para ejecutar

Tengo un programa maven, compila bien. Cuando corro mvn test no ejecuta ninguna prueba (en el encabezado TESTs dice There are no tests to run.).

He recreado este problema con una configuración súper simple que incluiré a continuación, así como la salida cuando se ejecuta con -X.

Las pruebas unitarias se ejecutan bien desde eclipse (tanto con su paquete junit predeterminado como cuando en su lugar incluyo el junit.jar downloaded by maven). También mvn test-compile crea correctamente la clase bajo test-classes. Estoy corriendo este en OSX 10.6.7 con Maven 3.0.2 y java 1.6.0_24.

Aquí está la estructura de directorios:

/my_program/pom.xml
/my_program/src/main/java/ClassUnderTest.java
/my_program/src/test/java/ClassUnderTestTests.java

Pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>my_group</groupId>
    <artifactId>my_program</artifactId>
    <packaging>jar</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>My Program</name>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.5</source>
                    <target>1.5</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Prueba de clase.java:

public class ClassUnderTest {

    public int functionUnderTest(int n) {
        return n;
    }

}

Class Undertesttests.java:

import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

public class ClassUnderTestTests {

    private ClassUnderTest o;

    @Before
    public void setUp() {
        o = new ClassUnderTest();
    }

    @Test
    public void testFunctionUnderTest_testCase1() {
        Assert.assertEquals(1, o.functionUnderTest(1));
    }

    @Test
    public void testFunctionUnderTest_testCase2() {
        Assert.assertEquals(2, o.functionUnderTest(2));
    }
}

Fin de la prueba mvn-X:

[DEBUG] Configuring mojo org.apache.maven.plugins:maven-surefire-plugin:2.7.1:test from plugin realm ClassRealm[plugin>org.apache.maven.plugins:maven-surefire-plugin:2.7.1, parent: sun.misc.Launcher$AppClassLoader@5224ee]
[DEBUG] Configuring mojo 'org.apache.maven.plugins:maven-surefire-plugin:2.7.1:test' with basic configurator -->
[DEBUG]   (s) basedir = /Users/aaron/Programs/my_program
[DEBUG]   (s) childDelegation = false
[DEBUG]   (s) classesDirectory = /Users/aaron/Programs/my_program/target/classes
[DEBUG]   (s) disableXmlReport = false
[DEBUG]   (s) enableAssertions = true
[DEBUG]   (s) forkMode = once
[DEBUG]   (s) junitArtifactName = junit:junit
[DEBUG]   (s) localRepository =        id: local
      url: file:///Users/aaron/.m2/repository/
   layout: none

[DEBUG]   (f) parallelMavenExecution = false
[DEBUG]   (s) pluginArtifactMap = {org.apache.maven.plugins:maven-surefire-plugin=org.apache.maven.plugins:maven-surefire-plugin:maven-plugin:2.7.1:, org.apache.maven.surefire:surefire-booter=org.apache.maven.surefire:surefire-booter:jar:2.7.1:compile, org.apache.maven.surefire:surefire-api=org.apache.maven.surefire:surefire-api:jar:2.7.1:compile, org.apache.maven.surefire:maven-surefire-common=org.apache.maven.surefire:maven-surefire-common:jar:2.7.1:compile, org.apache.maven.shared:maven-common-artifact-filters=org.apache.maven.shared:maven-common-artifact-filters:jar:1.3:compile, org.codehaus.plexus:plexus-utils=org.codehaus.plexus:plexus-utils:jar:2.0.5:compile, junit:junit=junit:junit:jar:3.8.1:compile, org.apache.maven.reporting:maven-reporting-api=org.apache.maven.reporting:maven-reporting-api:jar:2.0.9:compile}
[DEBUG]   (s) printSummary = true
[DEBUG]   (s) project = MavenProject: my_group:my_program:1.0-SNAPSHOT @ /Users/aaron/Programs/my_program/pom.xml
[DEBUG]   (s) projectArtifactMap = {junit:junit=junit:junit:jar:4.8.1:test}
[DEBUG]   (s) redirectTestOutputToFile = false
[DEBUG]   (s) remoteRepositories = [       id: central
      url: http://repo1.maven.org/maven2
   layout: default
snapshots: [enabled => false, update => daily]
 releases: [enabled => true, update => never]
]
[DEBUG]   (s) reportFormat = brief
[DEBUG]   (s) reportsDirectory = /Users/aaron/Programs/my_program/target/surefire-reports
[DEBUG]   (s) session = org.apache.maven.execution.MavenSession@dfbb43
[DEBUG]   (s) skip = false
[DEBUG]   (s) skipTests = false
[DEBUG]   (s) testClassesDirectory = /Users/aaron/Programs/my_program/target/test-classes
[DEBUG]   (s) testFailureIgnore = false
[DEBUG]   (s) testNGArtifactName = org.testng:testng
[DEBUG]   (s) testSourceDirectory = /Users/aaron/Programs/my_program/src/test/java
[DEBUG]   (s) trimStackTrace = true
[DEBUG]   (s) useFile = true
[DEBUG]   (s) useManifestOnlyJar = true
[DEBUG]   (s) workingDirectory = /Users/aaron/Programs/my_program
[DEBUG] -- end configuration --
[INFO] Surefire report directory: /Users/aaron/Programs/my_program/target/surefire-reports
[DEBUG] Setting system property [user.dir]=[/Users/aaron/Programs/my_program]
[DEBUG] Setting system property [localRepository]=[/Users/aaron/.m2/repository]
[DEBUG] Setting system property [basedir]=[/Users/aaron/Programs/my_program]
[DEBUG] Using JVM: /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/java
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for /Users/aaron/.m2/repository
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.apache.maven.surefire:surefire-booter:jar:2.7.1:compile (selected for compile)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.7.1:compile (selected for compile)
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-booter/2.7.1/surefire-booter-2.7.1.jar Scope: compile
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-api/2.7.1/surefire-api-2.7.1.jar Scope: compile
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for /Users/aaron/.m2/repository
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.apache.maven.surefire:surefire-junit4:jar:2.7.1:test (selected for test)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.7.1:test (selected for test)
[DEBUG] Adding to surefire test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-junit4/2.7.1/surefire-junit4-2.7.1.jar Scope: test
[DEBUG] Adding to surefire test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-api/2.7.1/surefire-api-2.7.1.jar Scope: test
[DEBUG] Test Classpath :
[DEBUG]   /Users/aaron/Programs/my_program/target/test-classes
[DEBUG]   /Users/aaron/Programs/my_program/target/classes
[DEBUG]   /Users/aaron/.m2/repository/junit/junit/4.8.1/junit-4.8.1.jar
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for /Users/aaron/.m2/repository
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.apache.maven.surefire:surefire-booter:jar:2.7.1:compile (selected for compile)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.7.1:compile (selected for compile)
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-booter/2.7.1/surefire-booter-2.7.1.jar Scope: compile
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-api/2.7.1/surefire-api-2.7.1.jar Scope: compile
Forking command line: /bin/sh -c cd /Users/aaron/Programs/my_program && /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/java -jar /Users/aaron/Programs/my_program/target/surefire/surefirebooter6118081963679415631.jar /Users/aaron/Programs/my_program/target/surefire/surefire4887918564882595612tmp /Users/aaron/Programs/my_program/target/surefire/surefire9012255138269731406tmp

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
There are no tests to run.

Results :

Tests run: 0, Failures: 0, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.089s
[INFO] Finished at: Mon May 30 12:03:09 EDT 2011
[INFO] Final Memory: 7M/62M
[INFO] ------------------------------------------------------------------------