How to include mod_ssl into httpd on rhel5.4

I'm trying to get apache running over https with mod_ssl on a rhel 5.4 x64 machine.

I don't have mod_ssl.so in the modules directory, nor can i find any ssl type output from httpd -M or httpd -l.

Yet if i run ldd against it i can see relevant shared library dependencies.

ldd /usr/sbin/httpd
  <blah>
  libcrypt.so.1 => /lib64/libcrypt.so.1 (0x00002b69cf11a000)
  libssl.so.6 => /lib64/libssl.so.6 (0x00002b69d1348000)
  libcrypto.so.6 => /lib64/libcrypto.so.6 (0x00002b69d1592000)

Do i need configure mod_ssl somehow to make it work as yum can't seem to find the relevent module to install itself.