I recommend releasing 5.1.4.Final with this fix.

I will see, if there are other things worth back-porting. Might make sense to do another 5.1 release

We're moving to Java 8 and I'm a little concerned that 5.2.0 will introduce a whole slew of Java 8 specific issues that will hinder our upgrade path

The whole intention of 5.2 is to be fully backwards compatible and just explore some new Java 8 features. I guarantee that there is no bug, but we took great care that all still works using Java 8 w/o utilizing any of the new features.

Of course, we could always downgrade to before this issue was introduced.

I'd give the upgrade a go, but I also explore another 5.1 release. I just don't want to promise a if and when yet.