SSL-VPN Client save Proxy Setzings

Hello,
I'm using Astaro V8,latest with SSL-VPN Client.
The Client use a proxy to connect with username, password.
Everything is working fine.
I figured out to save the connection user and pwd. KB 116185

How do I save the proxy user and pwd?
This seems not to work (with the astaro client?).

Thank a lot
Nathan