client:

- Fixed compile problem introduced by revision 2648.
- OpenSSL may not be found in /usr/lib64 if an old Cmake version is
  used => fall back to old library check added.


git-svn-id: https://xtreemfs.googlecode.com/svn/trunk@2649 f8528748-c2c0-11dd-ba5c-d3b7c2b3b534