signed jar를 같이 group으로 묶어 jar 파일 생성시..

http://stackoverflow.com/questions/999489/invalid-signature-file-when-attempting-to-run-a-jar

<target name="jar" depends="compile" description="Create one big jarfile.">
    <jar jarfile="${output.dir}/deps.jar">
        <zipgroupfileset dir="jars">
            <include name="**/*.jar" />
        </zipgroupfileset>
    </jar>
    <sleep seconds="1" />
    <jar jarfile="${output.dir}/myjar.jar" basedir="${classes.dir}">
        <zipfileset src="${output.dir}/deps.jar" excludes="META-INF/*.SF" />
        <manifest>
            <attribute name="Main-Class" value="com.mycompany.MyMain" />
        </manifest>
    </jar> 

</target>