cSipCfgSuspendResumeEnabled 1.3.6.1.4.1.9.9.152.1.1.1.13

This object specifies if support for handling Suspend/Resume events from the switch is enabled or not. If 'true', the user agent on getting a Suspend will notify the remote agent by sending it a re-invite with a hold SDP. Similarly, when the Gateway receives a Resume, it will initiate a re-invite with the original SDP and unhold the call. If 'false', the user agent will not initiate any re-invites on receiving Suspend/Resume events, basically it won't be putting the call on hold or off hold.