local_unbound update corrupts network accessibility!

After the unbound update - or coinciding this update in CURRENT - I have massive and
disturbing problems connecting to some sites, email servers and even the SVN server of
FreeBSD (ports and src).

For some name resoltions I receive

Host xxx.xxx.de not found: 2(SERVFAIL), while another domain then gets resolved without
problems.

The disturbing part is that this problem occured out of the blue and I connect it with
the update of unbound. It doesn't matter wether I use the old configuration or use a
stupid vanilla one. 

The blockage is also affecting Email. It takes a while until connections are made. Sites,
which could not resolved in the first place, get resolved after minutes, but then the
data transfer is bumpy or gets stuck.

I need to fix this. Boxes with older CURRENT than
FreeBSD 11.0-CURRENT #0 r269339: Thu Jul 31 20:47:17 CEST 2014 amd64 do not show this
nasty behaviour.

What is up with the system? I tried to follow the UPDATING, but there is nothing special
about essential changes. 

oh