Brekeke PBX conference problem

1. Brekeke Product Name and Version:

Brekeke PBX, Version 3.3.5.4 , Pro Evaluation

2. Java version:

3. OS type and the version:

windows 7 ultimate

4. UA (phone), gateway or other hardware/software involved:

Sipdroid(android phone)

5. Your problem:

first of all, sorry for i can not speak english well.

I am beginner brekeke PBX.

I want to make conference call, but it doesn't work.

Sipdroid Usernames are 1001, 2001, 3001.

I confirmed that 1 to 1 call is good. but, when I created conference

on server (extention number is 4001) and user called 4001,

user immediately received BYE request.

My conference setting is
: 1. auto invite attendees - 1001, 2001, 3001
2. Apply conf extension to From - no
3. Applied to (Caller numbers)* - 1001, 2001, 3001
4. Exit all when host leaves - no
5. Broadcast - no
6. Hang up existing calls - no

and I only use conference in NAT (also all sipdroid users are in NAT)

Sip server interface : 192.168.0.63

1001 - 192.168.0.64
2001 - 192.168.0.67
3001 - 192.168.0.35

do I have to add some settings?

please reply detailed explain

thank you for reading this problem

Have you checked the "5.12. Setting Up Conference Call" in the document?
http://www.brekeke.com/doc/pbx/pbx_admin_basic.pdf

Please update your PBX to version 3.3.5.8.
Version 3.3.5.4 has an issue with conference.

Lucy