About mail.pl
 

I have a mail.pl in my system , we never change this perl program , I want to know whether the program limit the no. of "to" address , if I use it to send to 1000 users , is it OK ? thx

No program won't limit. Howerver, your mail server may limit that. For example in my previous job I was working for web hosting company we have policy to limit 250 emails per domain outside world to avoid the spam. If it is your own server then processing 1000 mail is NOT a problem.