[PHP] more efficient alternative to mail()

Question regarding php's mail function. I've created a targetted mail system for a client, that uses the mail() function to send the the customer list. I find it's ok for a few hundred names, however the client has a list of over 1 and I know that would be way to taxing on the server, as s

[PHP] more efficient alternative to mail()

Question regarding php's mail function. I've created a targetted mail system for a client, that uses the mail() function to send the the customer list. I find it's ok for a few hundred names, however the client has a list of over 1 and I know that would be way to taxing on the server, as s