GMM: Adding Participant to a Role removes a different Participant instead: Jboss7

This has happened to me about 5 times today. I finally have captured evidence (attached screen shots).

In GMM:
- Find a Role that has existing Participants
- Select 'Add participant to a Role'
- Use the dropdown lists to select the AIPO to add
- Select 'Add'.

==> Rather than adding the selected AIPO as a Participant, instead, the last Participant in the existing list is deleted!!!

See the attached screen shots:

1. Notice that the last Participant in the Role is U-EYECARE/MOD_Model_II/None
2. Then I select U-EYECARE/AMI/None to Add
3. After selecting the "Add" button, you will see that U-EYECARE/MOD_Model_II/None was removed from the list of Participants, and U-EYECARE/AMI/None was not added.


This does not occur every time, but it has occurred multiple times today using both a Chrome and Firefox browser.

This also occurred with the RAD-5 Responder Role. When I tried to add a Participant from U-EYECARE, ***all 12 of the existing participants in the Role were deleted**!!

Note: this sounds like the problem reported a long time ago in GZL-916

The version was not on the list in Jira, but here it is from About:

TM version : 4.10.3
Build profile: gmm, mail-properties
Release Date : 25/03/15 11:30:24 CET