[Freeswitch-users] Verto call waiting

Hello, I'm trying to implement a verto call waiting (2nd call). I mean when I'm in a call and there's a second call to the same extension I need that verto client can take the second call and leave the first call on waiting. But I cannot complete this, I see on old mail https://lists.freeswitch.org/pipermail/freeswitch-users/2016-May/120422.html which says that on the same video tag dynamically is set. Do you have any examples of this? Any help would be appreciated. Thank you. Jose Figueroa