How to remove a user from a group?

Hi, I found the GroupService as in: context.getWiki().getGroupService(context).addUserToGroup(user, database, group, context); This GroupService interface allows me to locate users in a group and even add a user to a group. I don't see a method to remove a user from an XWiki group. How to do that in plug-in code? Regards, Gunter ------------------------------------------------------------------------------- Diese E-Mail enthaelt vertrauliche und/oder rechtlich geschuetzte Informationen. Wenn Sie nicht der richtige Adressat sind oder diese E-Mail irrtuemlich erhalten haben, informieren Sie bitte sofort den Absender und vernichten Sie diese Mail. Das unerlaubte Kopieren sowie die unbefugte Weitergabe dieser Mail ist nicht gestattet. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer. -------------------------------------------------------------------------------