The University of Winnipeg maintains a number of PPDs including Crypt-SSLeay.ppd. Check out http://theoryx5.uwinnipeg.ca/ppms for a full list of ppds for Activestate 5.8.x. This repository also has Activestate 5.6.x compatible ppds at http://theoryx5.uwinnipeg.ca/ppmpackages/

You should be able to install using the following command line ppm3 install http://theoryx5.uwinnipeg.ca/ppms/Crypt-SSLeay.ppd