某些Python模块（如）lxml在C中具有必需的组件。它们在Jython中不起作用。

大多数Python软件包都可以正常运行，你可以使用与CPython相同的工具来安装它们。在Jython Book的附录A中对此进行了描述：

要获得setuptools，请从http://peak.telecommunity.com/dist/ez_setup.py下载ez_setup.py 。然后，转到你保留下载文件的目录并执行：

$ jython ez_setup.py

[easy_install脚本将被安装]安装到Jython安装的bin目录中（/home/lsoto/jython2.5.0/bin在上面的示例中）。如果你经常使用Jython，则最好将此目录添加到PATH环境变量之前，这样就不必每次都要使用easy_install或其他安装到此目录的脚本时都键入整个路径。

在Jython中安装setuptools之后，我自己进行了测试，正确安装了pip：

$ sudo /usr/bin/jython2.5.2b1/bin/easy_install pip
Searching for pip
[...]
Installing pip-2.5 script to /usr/bin/jython2.5.2b1/bin
Installing pip script to /usr/bin/jython2.5.2b1/bin

Installed /usr/bin/jython2.5.2b1/Lib/site-packages/pip-1.0.2-py2.5.egg
Processing dependencies for pip
Finished processing dependencies for pip

$ sudo /usr/bin/jython2.5.2b1/bin/pip install bottle
Downloading/unpacking bottle
  Downloading bottle-0.9.6.tar.gz (45Kb): 45Kb downloaded
  Running setup.py egg_info for package bottle
    Installing collected packages: bottle
  Running setup.py install for bottle
Successfully installed bottle
Cleaning up...

$ jython
Jython 2.5.2b1 (Release_2_5_2beta1:7075, Jun 28 2010, 07:44:20) 
[Java HotSpot(TM) 64-Bit Server VM (Apple Inc.)] on java1.6.0_26
Type "help", "copyright", "credits" or "license" for more information.
>>> import bottle
>>> bottle
<module 'bottle' from '/usr/bin/jython2.5.2b1/Lib/site-packages/bottle$py.class'>
>>>