David Fronk wrote on Tuesday, July 01, 2008
received word from Microsoft that they have an update available to fix an issue that occurs with the email router. For whatever reason the email router will poll for an hour and then lock for an hour. If it unlocks itself after that second hour it will work for another hour and then lock itself again. The hour comes from the default polling time that is set up in the email router config file. So, if you were to modify that polling time then you would extend the life of your email router from locking up but also extend the amount of time to get the email router back up once it is locked.
I used a work around to get by until this hotfix became available by restarting the email router service each hour via a bat script.
However the hotfix you want to check out is KB article 952019. You will need to contact Microsoft via PartnerSource or CustomerSource in order to obtain the hotfix, but you will not be charged for the ticket if you are requesting the hotfix.
Hope this comes in handy for someone else as well.