You probably need more packages. Install libjpegthat includes /usr/lib/libjpeg.so*and try again.
In my Fedora (other version), PIL is installed using python-imagingrpm:
ldd _imaging.so
linux-gate.so.1 => (0x004c6000)
libjpeg.so.62 => /usr/lib/libjpeg.so.62 (0x00a07000)
libz.so.1 => /lib/libz.so.1 (0x00b91000)
libpython2.5.so.1.0 => /usr/lib/libpython2.5.so.1.0 (0x00110000)
libpthread.so.0 => /lib/libpthread.so.0 (0x00ee8000)
libc.so.6 => /lib/libc.so.6 (0x00260000)
libdl.so.2 => /lib/libdl.so.2 (0x003c9000)
libutil.so.1 => /lib/libutil.so.1 (0x00fcd000)
libm.so.6 => /lib/libm.so.6 (0x00ad1000)
/lib/ld-linux.so.2 (0x007a1000)
, PIL libjpeg.so.