I remember that thread... That was brought up over on GoogleGroups awhile back.
Here is what was discussed:
Remko's Post
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Several possibilities spring to mind, in order of preference:
- First, I would look if it isn't easier to reconfigure the other systems to send snmp traps or (sys)log messages instead. Email is unreliable, free format (which makes it difficult to interpret), and needs a lot of intermediate infrastructure (mail servers), introducing multiple points of failure. Most systems that can send emails can also send alarms in other formats.
- You could write a simple probe to retrieve emails from a POP3 mailbox and turn them into alarms. The POP3 protocol is very simple.
- If you use sendmail (and probably some mail clients as well), the incoming mailbox is a directory on disk. The files in that directory are human readable. You might try to use logmon to read such files.
- The Exchange_response probe has an option to "alert on unknown messages". Not sure if that will include the text in the alert, and how elegant it will be, but it's an option.
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Adrian Later Posted
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Thanks for the Prototype Remko, I've used this as the basis for the probe I've created...
Also like to thank Richard for your "Customer Connect Create Custom Probes Effortlessly" training session!!
I have uploaded 2 files to Google groups, "email2alarm User Guide.pdf" & "email2alarm_1.00.zip"
Basically the probe poll's an Email account via Pop3, if any emails are found then it downloads them, creates an alarm in NMS and then deletes the email from the Pop3 account.
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Unfortunately, the actual Probe isn't accessible from Groups now, the User Guide is but that's obviously fairly useless without the actual script. 
I've emailed Adrian asking if he could chime in here and share his script.
Dustin