Pair to NX3000

[ghost]

Hi,
I'm trying to pair to an NX3000.
So far without luck.
I'm sending the following command:
curl -GET -v --user-agent "SEC_MODE_ac:d1::::" "http://192.168.107.1:7788/mode/control" -d ""
with the full mac-address.
This is the curl output:
Trying 192.168.107.1...

• TCP_NODELAY set
• Connected to 192.168.107.1 (192.168.107.1) port 7788 (#0)

GET /mode/control? HTTP/1.1
Host: 192.168.107.1:7788
User-Agent: SEC_MODE_ac:[...]
Accept: /

< HTTP/1.1 503 Service Unavailable
< Server: SEC Mode Server
< Operation-Mode: RVF
< Default-URL: unavailable

• no chunk, no close, no size. Assume close to signal end
  <
• Closing connection 0

Can somebody point me in the right direction?

Thanks
Jan