• Create a configuration file according to the XML file format e.g. gruu.cfg
• File content:
  

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>

<!-- Generated by sipXecs: http://www.sipfoundry.org/

Instructions for integrating new configuration file content into sipXconfig:
http://wiki.sipfoundry.org/display/xecsdev/Adding+Polycom+SoundPoint+IP+New+Configuration+File+Content+into+sipXconfig
-->
<polycomConfig xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="polycomConfig.xsd">

<reg reg.1.gruu="1"/>

</polycomConfig>

• Upload the file either manually to /var/sipxdata/configserver/phone/profile/tftproot/ or through the Admin Portal -> Devices -> Device files
• Apply this configuration files to the desired devices: Devices -> Phones -> <MAC> -> Custom configuration and fill in the name of the file (e.g: gruu.cfg)
• Send profiles

Note: This will be improved as to be configurable from Admin Portal per device

Documentation on GRUU :http://tools.ietf.org/html/draft-ietf-sip-gruu-15