How to allow users to connect to Oracle Instant Messenger without appending domain to the username while logging in?

Step 1:
Login to the Oracle Collaboration Suite Middle tier where the Oracle RTC has been
installed. Navigate to $ORACLE_HOME/imeeting/bin

Step 2:
Issue the following command

$ rtcctl setproperty –system true –pname IMDomainNames –pvalue "Press ENTER"
“[\”ACTUAL_MID_TIER_RTCSERVER_HOSTNAME\”]”

For e.g
$ rtcctl setproperty –system true –pname IMDomainNames –pvalue
“[\”hostname.com\”]”

Step 3:
Restart the RTC Server
$ rtcctl stop
$ rtcctl start

Now the users should be able to login to Oracle Instant Messenger without appending the hostname (marked in blue in the picture as shown below) while logging in.