+--with-pam enables PAM support.
+
+--enable-gnome-askpass will build the GNOME passphrase dialog. You
+need a working installation of GNOME, including the development
+headers, for this to work.
+
+--with-prngd-socket=/some/file allows you to enable EGD or PRNGD
+support and to specify a PRNGd socket. Use this if your Unix lacks
+/dev/random and you don't want to use OpenSSH's builtin entropy
+collection support.
+
+--with-prngd-port=portnum allows you to enable EGD or PRNGD support
+and to specify a EGD localhost TCP port. Use this if your Unix lacks
+/dev/random and you don't want to use OpenSSH's builtin entropy
+collection support.
+
+--with-lastlog=FILE will specify the location of the lastlog file.
+./configure searches a few locations for lastlog, but may not find
+it if lastlog is installed in a different place.
+
+--without-lastlog will disable lastlog support entirely.
+
+--with-osfsia, --without-osfsia will enable or disable OSF1's Security
+Integration Architecture. The default for OSF1 machines is enable.
+
+--with-kerberos4=PATH will enable Kerberos IV support. You will need
+to have the Kerberos libraries and header files installed for this
+to work. Use the optional PATH argument to specify the root of your
+Kerberos installation.
+
+--with-afs=PATH will enable AFS support. You will need to have the
+Kerberos IV and the AFS libraries and header files installed for this
+to work. Use the optional PATH argument to specify the root of your
+AFS installation. AFS requires Kerberos support to be enabled.