Purge incorrect email address members?

[ncangler]

If there is already a mod for doing this please let me know. I have about 4200 members on two sites with about 30-35% of them regularly active. I know that there are a number of members who have either entered their email address incorrectly or it has changed and they have not updated it. Is there a way to periodically check for valid, active email addresses and if one is not valid send a PM asking the member to check their email address in their User CP settings and after a period of time or attempts, delete the user account? The testing of the email on record could be done each time an email is sent out to the membership list.

I'm looking for a way to eliminate all the undeliverable emails I get from thread notifications and birthday emails without purging members unnecessarily. What do you think?