maven-source-plugin not work for kotlin

I am trying to use maven-source-plugin to create a source.jar for my kotlin project, but seems the maven-source-plugin not work well for kotlin project.

when i run "mvn source:jar", the output message always says:

[INFO] No sources in project. Archive not created.

here is the maven-source-plugin configuration in my pom file of the project:

    <build>
    <plugins>

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-source-plugin</artifactId>
            <version>2.2.1</version>
            <executions>
                <execution>
                    <id>attach-sources</id>
                    <phase>package</phase>
                    <goals>
                        <goal>jar</goal>
                    </goals>
                    <configuration>
                        <attach>true</attach>
                        <includes>
         <!-- i am trying to specify the include dir manually, but not work -->                               
                         <include>${project.basedir}/src/main/kotlin/*</include>
                        </includes>
                        <forceCreation>true</forceCreation>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

my question is: how to attach kotlin source files using maven-source-plugin?

thanks ~~

By default maven expects sources to be in src/main/java directory. If you use non-default directories, you have to specify them in build element:

<build>
    <sourceDirectory>src/main/kotlin</sourceDirectory>
    <testSourceDirectory>src/test/kotlin</testSourceDirectory>
</build>