Certificate search not working after upgrade

We are using GPG4win v2.1.0 on a windows XP SP3 environment. Yesterday we upgraded to GPG4Win v2.2.1 (latest).
We noticed that the search for a certificated crashes Kleopatra. In the old version we didn’t have this issue. Does someone has a clue how we can solve this?

Hi Tobi,
thanks for your report.
Can you help us to reproduce this into a qualified report so that our
developers can act on it?

Certainly the application should not crash.