I have installed php5 in my ubandu.I am using graph api to commuicate with facebook.But i am getting the error like "Facebook needs the CURL PHP extension".I know that i have to add "extension=php_curl.dll" line in the php.ini file.but the existing ini file is not having any extension. And there is no file called "php_curl.dll".
I assume, you have ubuntu linux. Try this:
sudo apt-get install php5-curl
See also Ubuntu Forum And afterwards restart your apache.
Normally, in Linux extensions are not called .dll, but ".so". Afaik, .dll is Windows specific.