Here is the relevant section of the Makefile.PL that generates the error:

while (1) {
    $exe_path = "$openssl_path/bin/openssl";
    last if -x $exe_path;
    $exe_path = "$openssl_path/bin/openssl.exe";
    last if -x $exe_path;
    $exe_path = "$openssl_path/sbin/openssl";
    last if -x $exe_path;
    $exe_path = "$openssl_path/out32dll/openssl.exe";
    last if -x $exe_path;

    print "I could not find your OpenSSL in `$openssl_path'\n";
    print "Please provide OpenSSL-$openssl_vers or\n"
    . "OpenSSL-$openssl_vers2 installation directory (get from\n"
    ." http://www.openssl.org/ if you don't have it; please note that\
+n"
        ." SSLeay is no longer supported, see README) (C-c to abort):\
+n";
    $openssl_path = <STDIN>;
    chomp $openssl_path;
}
[download]

If the openssl executable is in /usr/bin, then the path you need to pass to the Makefile.PL is simply '/usr' - not '/usr/bin/openssl' or '/usr/bin'.

If, on the other hand, the openssl executable is located in '/usr/bin/openssl/bin', then passing '/usr/bin/openssl' is correct. In that case the failure could be that the '-x' condition (being tested in the Makefile.PL) is not being satisified and you should try to work out why that failure occurs.

If you still can't get anywhere with this could you tell us the name of the openssl executable, and its location. (I gather from your post that '/usr/bin' is the location, and that the name of the executable file is 'openssl' - but I'm not completely certain that I've got that right :-)

Cheers,
Rob