请问一下，ant里面怎么引用第三方jar包啊？

想帮测试弄个简单点的替换代码的方法的。结果就卡死了。忧郁~~

报错提示如下：
BUILD FAILED
/home/noc/workspace/22/build.xml:39: The following error occurred while executing this line:
/home/noc/workspace/22/build.xml:23: Problem: failed to create task or type sshexec
Cause: the class org.apache.tools.ant.taskdefs.optional.ssh.SSHExec was not found.
This looks like one of Ant's optional components.
Action: Check that the appropriate optional JAR exists in
-/usr/share/ant/lib
-/root/.ant/lib
-a directory added on the command line with the -lib argument

Do not panic, this is a common problem.
The commonest cause is a missing JAR.

This is not a bug; it is a configuration problem

贴上build.xml 里的内容

    <property name="TEMPDIR" value="./temp"></property>
    <property name="HOST" value="192.168.2.203"></property>
    <property name="USER" value="root"></property>
    <property name="PASSWD" value="VoX8J80g"></property>

    <target name="prepare">
            <delete dir="${TEMPDIR}"></delete>
            <mkdir dir="${TEMPDIR}"/>
    </target>

    <target name="packgesrc">
            <zip destfile="${TEMPDIR}/src.zip">
                    <zipfileset dir="./src" />
            </zip>
    </target>

    <target name="uploadsrc">
            <sshexec host="${HOST}" username="${USER}" password="${PASSWD}" trust="true" command="
                    rm -rf /home/noc/src;
                    mkdir /home/noc/src
                    "/>
            <scp todir="${USER}:${PASSWD}@${HOST}:/home/noc/src/" file="${TEMPDIR}/srczip" trust="true"></scp>
            <sshexec host="${HOST}" username="${USER}" password="${PASSWD}" trust="true" command="
                    cd /home/noc/src/;
                    unzip src.zip;
                    rm -rf src.zip;
                    "/>
    </target>

    <target name="clear">
            <delete dir="${TEMPDIR}"></delete>
    </target>

    <target name="call">
            <antcall target="prepare"></antcall>
            <antcall target="packgesrc"></antcall>
            <antcall target="uploadsrc"></antcall>
    </target>

根据报错信息，是因为ant缺少jar包，后来网上找了jar包，放到提示里面的目录下了，报错还是一样的。
后来搜了网上的解决方案，各种设置path和classpath，还是没用。

黔驴技穷~~
求神通广大的it友们帮忙解决啊。

把你需要的jar包放到你的jdk/jre/lib/ext文件夹下即可解决