You can add this snippet to your pom.xml (from the link published by @Jörn Horstmann):
<pluginManagement>
            <plugins>
                <!--This plugin's configuration is used to store Eclipse m2e settings 
                    only. It has no influence on the Maven build itself. -->
                <plugin>
                    <groupId>org.eclipse.m2e</groupId>
                    <artifactId>lifecycle-mapping</artifactId>
                    <version>1.0.0</version>
                    <configuration>
                        <lifecycleMappingMetadata>
                            <pluginExecutions>
                                <pluginExecution>
                                    <pluginExecutionFilter>
                                        <groupId>org.apache.cxf</groupId>
                                        <artifactId>cxf-codegen-plugin</artifactId>
                                        <versionRange>[2.3.3,)</versionRange>
                                        <goals>
                                            <goal>wsdl2java</goal>
                                        </goals>
                                    </pluginExecutionFilter>
                                    <action>
                                        <execute />
                                    </action>
                                </pluginExecution>
                            </pluginExecutions>
                        </lifecycleMappingMetadata>
                    </configuration>
                </plugin>
            </plugins>
        </pluginManagement>
The more important lines are:
<groupId>org.apache.cxf</groupId>
                                        <artifactId>cxf-codegen-plugin</artifactId>
                                        <versionRange>[2.3.3,)</versionRange>
                                        <goals>
                                            <goal>wsdl2java</goal>
                                        </goals>
So, you have to ensure what version of CXF are you using...
Hope this can help...