There are a lot of posts out that say to install the libraries jpeg and jpeg-devel prior to installing PIL, but this did not work for me on Cento. For example this site http://www.jroller.com/RickHigh/entry/installing_pil_python_image_library suggests using the command:

$ sudo yum install freetype freetype-devel jpeg jpeg-devel libpng libpng-devel
Setting up Install Process
Setting up repositories
Reading repository metadata in from local files
Parsing package install arguments
No Match for argument: jpeg <No Match for argument: jpeg-devel <Resolving Dependencies
–> Populating transaction set with selected packages. Please wait.
—> Downloading header for libpng to pack into transaction set.
……

Instead use:

$ sudo yum install freetype freetype-devel libpng libpng-devel libjpeg libjpeg-devel

If you have already got as far as installing PIL, delete it from the site-packages directory and reinstall, I use easy_install PIL, and this will rebuild PIL, this time with jpeg support.

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*** TKINTER support not available
— JPEG support available
— ZLIB (PNG/ZIP) support available
— FREETYPE2 support available
*** LITTLECMS support not available
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