Each operating system where the MTA runs provides tools for monitoring programs.
If you are running the MTA on NetWare servers, you can use the NetWare Monitor NLM to monitor the effects of the MTA on the NetWare server. NetWare 6.x provides monitoring tools that you can use from your Web browser. Processor, resource, and memory utilization can be compared to other non-GroupWise NLM programs to determine if the MTA NLM program is monopolizing resources. See your NetWare documentation for additional monitoring suggestions.
If you are running the MTA on Linux servers, you can use SNMP tools like snmpget and snmpwalk that allow you to retrieve the data about all the services registered with the SNMP service. These tools are part of the NET-SNMP package. See your Linux documentation for additional monitoring suggestions.