maven and multiple projects

If you are having issues with the plugin finding the project file...use the full path to the project file first and see if that works. If it works then you know that it is the relative path that is the issue.

I am also noticing that you are not defining a maven phase to run the maven soapui plugin during. You also are not defining the goal in the maven soapui plugin that you want to run.

ie.

<executions>
                    <execution>
                        <id>qa</id>
                        <phase>integration-test</phase>
                        <configuration>
                            <projectFile>${pom.basedir}/src/test/soapui/MyProject-soapui-project.xml</projectFile>
                        </configuration>
                        <goals>
                            <goal>test</goal>
                        </goals>
                    </execution>
                </executions>