[gabrielt]

Installation of this mod requires that your cURL installation to have support for SSL, in order for your server to be able to exchange information with Facebook...

You must download and compile openSSL: http://www.openssl.org/
You have to download and compile libcurl: http://curl.haxx.se

OpenSSL MUST be configured with --shared (otherwise you will get the message "configure: error: OpenSSL libs and/or directories were not found where specified!" when configuring cURL):

./configure --shared
make
make test
make install

Had to install libssl-dev (apt-get install libssl-dev).

Then configure and compile cURL with:

./configure --with-ssl
make
make install