A new release with an interim improved email system is now available. If your installation has processed more than 100,000 emails, the email numbers are being reused and you need this update to avoid unnecessary email deletions and to maintain email privacy.
It's "interim" because there is a better solution in the works, but that will take a few weeks to implement. One user has already experienced the problem, and this fix takes care of them.
I've corrected an error in the Makefile (a missing " after the version string) which caused compilation to fail with a very strange message. Anyone who downloaded the 4.1.71 release and who didn't find this error for themselves should download again.