Problem with sendmail

We are using web application which is hosted on Solaris server(Solaris OS 5.10). This application contains some feedback form and contact us form, which should trigger email to our web admin once those are submitted by users.

This forms are integrated with mailmerge.cgi utility(perl utility) which uses sendmail to trigger emails. Our web admin not receiving emails nowadays.

  1. sendmail service in the unix server running.
  2. We tested sending email from unix box using sendmail and mailx command, we are receiving the mails.
  3. Sendmail log is not configured to log on "/var/log/mail.log" and all the sendmail logs coming to syslog file.
  4. We do not see syslog file for few weeks.

Kindly help us to know where the mails are blocked.