Backport Acorn deadlock fix for release/1.32.0.2 branch
The original problem is https://www.simantics.org/redmine/issues/7713 which was fixed for release/1.34.0
10 months ago. It was never picked for this branch for Apros 6.08 because its release was too near, however, we should have picked it for 6.08 SR1 later on.