the first part i dont have an answer to. but where i would check to start with is your hosting provider. if they have a firewall or any type of security on the server, this could block your mail from being sent. as this script is goin to send it out as nobody from the server. i too had this problem, and had to slacken up on my firewall settings and hack up the nobody clause so that mail could be sent from the server via scripts.
now as for the 2mb thing. what type of server are you hosting on? shared, dedicated, vps? suphp phpexec phpcgi? just need some information in order to better assist you.
later,
DosDawg
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