Unable to set logging for JIRA Wallboard Plugin permanently in log4j.properties

Steps to Reproduce:

1. install JIRA wallboard plugin.
2. got to the dashboard and click on the Tools > View as Wallboard.
3. check the logs to find the following lines:

    2014-06-12 21:58:30,345 http-bio-7625-exec-17 INFO admin 1318x143x1 vnimab 10.60.5.147 /plugins/servlet/Wallboard/ [atlassian.jirawallboard.servlet.WallboardServlet] Session id is: 0AAB676DD1908CEFC39253569A7C3593 

4. stop JIRA.
5. Find the file in JIRA Installation Folder > atlassian-jira > WEB-INF > classes > log4j.properties.
6. edit the file and add another logging properties inside for JIRA Wallboard plugin:

   log4j.logger.com.atlassian.jirawallboard.servlet.WallboardServlet = WARN, console, filelog
   log4j.additivity.com.atlassian.jirawallboard.servlet.WallboardServlet = false
   

7. start JIRA and view the dashboard on wallboard again.

Expected Result:
Any logging below WARN will not be appearing on the logs.

Actual Result:
The INFO logs still appearing in the logs:

 2014-06-12 21:58:30,345 http-bio-7625-exec-17 INFO admin 1318x143x1 vnimab 10.60.5.147 /plugins/servlet/Wallboard/ [atlassian.jirawallboard.servlet.WallboardServlet] Session id is: 0AAB676DD1908CEFC39253569A7C3593 

Note:

• The logging will be possible to be set up only on UI (Logging and Profiling)
• After refresh, the logging level change back from WARN to ALL.