SM build 7125 was not affected.
The problem appeared in custom build 7139 that we had to install to fix newsletter issues after customer complaints.
I opened a ticket explaining precisely the issue (same as bruce is describing here), that was 20 july (1 month ago).
I also specified in follow-ups that it appeared after build 7139 installation, so they are aware of it, to better locate the code changes that could be the source of the problem.
After a few support ping-pong resulting in new custom build to install the problem is still here.
In the meantime 7153 was publicly released containing the problem... ( I really don't get it why they released a public version with a _known_ major issue )
Since a month we're spending an unbelievable amount of time each day to monitor/clean spool of these NDR before queue starts to be filled with 100K and more of these FAIL mails and creating locking problems on the mailboxes, and even server lockups...
Everybody is angry and tired here, our tech staff, our customers (threating to use another service...)
This really need to be top 1 issue to be resolved.
Sébastien Riccio
System & Network Admin
https://swisscenter.com