[CentOS] sendmail stops accepting e-mail after sending 40 to 50 messages

Mon Mar 11 08:30:15 UTC 2013
pedro figueiredo <pedro at t3k.pt>

i have a centos box (vps) with sendmail and i'am using it to 
send a newsletter to mail clients. 

I'am using a machine in my local network to send the e-mails 
via SMTP (AUTH PLAIN) but after sending some e-mail (35 .. 50) 
the connection starts to get closed by the server 
(centos/sendmail)

I've searched google for a limit configuration on number of 
e-mails in sendmail but didn't find anything.

any ideias on what configuration can i use to allow me to 
send more e-mails?