Hi,has anyone known how to send a lot of emails at one click by JavaMail(mail.jar,activation.jar),say 500-5000 volume.

what I do:
1.new one thread
2.in the thread,loop for all persons and get their email-address and then send email one by one:

I find the procedure could apply to 20-30 volume,but failed to apply to 500-5000 volume

thanks in advance