I forked this to add my quick-and-dirty addition to export contact photos into vcards.
Tested with a .pst from Outlook 2003 and importing into GMail.
I read somewhere that attachments on contacts aren't always photos, so let me know if
this doesn't work for you.

My command was
readpst -tc -cv Outlook.pst

There will now be a file named Contacts that is a vcard file with your contacts, including
their photos.

Starting with a mercurial working directory, try this:

    make -f *cvs
    (cd xml; make; make distclean)
    make distcheck

    ./configure
    make
    su
    make install