ntpq traceback on macOS

Dear Support Team,

I pulled commit b988855d from gitlab.com/NTPsec/ntpsec.git
OS is macOS 10.12.6 (16G29)
I upgraded recently from 10.12.5 to 10.12.6

I complied ntpsec with the following steps. ( As done several times before )

export LDFLAGS="-L/usr/local/opt/openssl/lib"
export CFLAGS="-I/usr/local/opt/openssl/include"
export PYTHONPATH=/usr/local/lib/python2.7/site-packages/ntp

./waf clean
./waf configure 
./waf build 
sudo ./waf install

This was successfully without any warning.
But when I run ntpq I get a traceback

 
mayer (master) ntpsec $ /usr/local/bin/ntpq -c ver 
Traceback (most recent call last):
  File "/usr/local/bin/ntpq", line 28, in 
    import ntp.packet
  File "/usr/local/lib/python2.7/site-packages/ntp/packet.py", line 775, in 
    class ControlSession:
  File "/usr/local/lib/python2.7/site-packages/ntp/packet.py", line 779, in ControlSession
    ntp.control.CERR_UNSPEC: "UNSPEC",
AttributeError: 'module' object has no attribute 'CERR_UNSPEC'

Kind regards
Hans