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