Authentication slow with Sendmail
 

System Setup:
HP DL380 G3
RedHat 8.0
Default Sendmail Install from Redhat/Has been updated using Up2date.
1xpublic Nic
1xprivate Nic


Heres my problem:

Using RedHat 8.0 I've created a multi-purpose server for the company I work for. The server provides FTP, POP3, SMTP, and IMAP services. All of them are working like they should be with the exception of Sendmail. Well it is and it isn't. Let me explain.

We have several nodes in our network set up to automate tasks that need to be done, one of them is emailing reports to clients. The program used was created in-house and works great. What is happening is about 30-40% of the time the automation PC goes to authenticate when sending mail and it times out. As a temp solution we modified the programs settings to allow a total of 90 sec timeout period when connecting to the SMTP server. As you can see this will indefinitely cause problems the more unique emails that are generated. Eventually we will need to set up an additional PC to generate email in parallel with the other PC, and I'm not sure that won't cause problems. What is causing the long authentication time? Is there a way to improve it?

Thanks for any help.