Step 1:

Log in to your KAS (Technical Administration) panel and click on Tools -> DNS Settings.

Click the Edit icon right next to the domain and then click on Add a new DNS record.

Step 2:

Example entry: _chat._tcp.your-domain.com 43200 IN SRV 10 0 5236 exampleserver.com.

The caching time (43200) cannot be altered. The Name is _chat._tcp and the Priority is 10. As Type please select SRV and in the Data field please enter 0 5236 exampleserver.com

Click on Save.

Explanation:
*The name of the service is chat.
*The transport protocol is TCP. But it can also be UDP, SCTP or TLS.
*The caching time or time to live (TTL) is 12 hours (43,200 seconds).
*The class is IN.
*The type is SRV.
*The priority is 10. In the case of multiple SRV records the priority specifies the order of the proxy queries. Lower values will be queried first.
*The weight is 0. In the case of multiple SRV records with the same priority, the weight proportionally determines how often the target should be queried.
*The port is 5236.
*The target/destination server is exampleserver.com

Step 3:

The new entry will now show up in the table.

IMPORTANT: After the change it could take up to 3 or 4 hours until the new settings are active.