http://www.lothar.com/tech/crypto/
+GNU Make:
+ftp://ftp.gnu.org/gnu/make/
+
+OpenSSH has only been tested with GNU make. It may work with other
+'make' programs, but you are on your own.
+
+PCRE (PERL-compatible Regular Expression library):
+ftp://ftp.cus.cam.ac.uk/pub/software/programing/pcre/
+
+Most platforms do not require this. However older Unices may not have a
+posix regex library. PCRE provides a POSIX interface.
+
S/Key Libraries:
http://www.sparc.spb.su/solaris/skey/