JAVA Mail API

[ssmtech]

Hello All,             I am using Javamail API to send email through my application running on J2EE application server...and i will be sending 1000's of email every day... Sometimes javamail is not able to send all the emails even though the email addresses are proper...   For example...if i send 300 emails to the SAME email addresses(to my email address) then i receive only 200 or so..but not all....but if i try the same thing again after some day then i receive all of them.....   So my question is that, is there a Bug with the JavaMail API ,if the email addresses grow too large...or is it with the SMTP Server which i am using.....("smtp.roltanet.com") If their is some thing  with the SMTP server,how do i improve the performance of my application by sending 1000's of email every day....   Please suggest me some solution....   Thanks a million in advance   Sam