Custom mail handler logging

[aas]

I have INFO logging level in log4j.properties for incoming mail

 But in atlassian-jira-incoming-mail.log I have logs with DEBUG level like this

DEBUG Found 1 unprocessed message(s) in the pop3 folder
DEBUG Processing message
DEBUG TOP 1 0
DEBUG +OK
DEBUG Closing folder

And there it isn't from mail handler plugin but mail protocol logs.  How I have to configure log4j to see logs from my custom mail handler plugin? I need make some changes in log4j.properties file or in logging and profiling in Jira UI?