using a proxy by default

["kranthi uppalapati" <kranthi117@xxxxxxxxx>]

my ISP uses a firewall to block all the ports except port 80
i hav to use a locally hosted server and the site must be accessible only inside the network.
but i want to access an external SMTP server for php mail function.
the intention being to send a confirmation mail to the registered users.
i use a socks proxy in the mail client  to get past the firewall
how can i do it by php..

i use a proxy server to connect to the internet. i hav to use it to access any computer outside my network. plz dont suggest me to use CURLOPT_PROXY.. i don't want it to do every time. i want php to access the proxy every time it access a url. especially while using third party scripts i don't want to go through the entire code and make the changes just for proxy.

if possible i also want to keep php from accessing the proxy server while accessing the sites inside the network