Building with mvn install -Dmaven.test.skip=true failes

Just wanted to build one more time axis2 from the trunk, with -Dmaven.test.skip=true
That worked well for me in the past as I started to not run all the tests as they seldom where running and where too often the cause for a abort of the build.
Now even with -Dmaven.test.skip=true it failed. The reason is a missing file which is not generated if tests are skipped.

<plugin>
<artifactId>maven-antrun-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>run</goal>
</goals>
<phase>test</phase>
<configuration>
<tasks unless="maven.test.skip">
<echo message="Generating p2n.wsdl" />

<java classname="org.apache.ws.java2wsdl.Java2WSDL" classpathref="maven.test.classpath" fork="true" failonerror="true">
<arg value="-o" />
<arg value="${project.build.directory}/java2wsdl" />
<arg value="-of" />
<arg value="p2n.wsdl" />
<arg value="-cn" />
<arg value="org.apache.axis2.description.CalculatorService" />
<arg value="-p2n" />
<arg value="[org.apache.axis2.description,http://www.example.org/calculator]" />
<arg value="-stn" />
<arg value="http://www.example.org/calculator-service" />
</java>
</tasks>
</configuration>
</execution>
</executions>
</plugin>

The file p2n.wsdl is missing as it will be not generated if -Dmaven.test.skip=true is selected.
Why is that file not generated when I just intend to not have tests?

Josef