PHP fsockopen not working for non port 80

Question

I have a simple PHP script. It works for any external IP on port 80 but any other port fails. I'm assuming it has to do with the host, so what am I missing to be able to check ports other than 80?

Answer 1

Most hosting systems prevent outgoing connections on other ports than 80 to prevent abuse, for example botscripts connecting to IRC servers or spamscripts connecting to SMTP hosts on 25.

Example hoster explanation.