How many emails are you trying to send? If its just a few or a couple (like to yourself and a confirmation to user) you could use Swiftmailer and PHP to do this. You just envoke two instances of the mail transport fuction (similar to sendmail()) one right after another in your php code and you are good to go.
Here is an excellent tutorial. It is about sending an html email with pdf attachment but they also cover sending to more than one recipient.
Hope that helps,