here is a short info to resolve a race condition between our newsletter sendout and the very latest production build:
We got informed about a serious (blocker) bug with a deadlock in committed callbacks after our newsletter had already been released to marketing: COR-1377
This bug received the highest priority and it has has been fixed immediately.
A new production build with the build number 7.4.58.11547 is online in the meanwhile. If you downloaded 7.4 right after the newsletter and if you use committed callbacks or UUIDs, we recommend to check the build number you are using (call Db4o#version() / Db4oFactory#Version() ) and to download the very latest build once again if it is lower than 7.4.58.
To our knowledge this bug has been present in all 7.2 builds.