How to get empty groups using Smack?

Currently I am using Smack for my client to use with Jabber Cisco server. I have problem with getting empty groups (desktop client from cisco is be able to retrieve these empty groups). I saw the old thread with same issue https://community.igniterealtime.org/thread/15863#108282 but not have answer yet. I am using Smack v. 4.1.3 and still have the same issue. I am wondering that I missing something while using Smack or this is a limitation of Smack?

Thank you,

Phuong

XMPP has no concept allowing for empty Roster groups. Those are simply not possible with XMPP.

Thank you for your reply! Do you have any idea (any way) that we can get empty groups?

Thanks,

Phuong