warning: can't set group name to 'avmail'

Does anyone know why I am getting this warning. Everything is scanning fine on postfix but I am seeing this warning in the avastd.log

Apr 23 14:34:11 avastd[3590]: warning: can’t set group name to ‘avmail’, Operation not permitted

Apr 23 14:34:11 avastd[3586]: info: started new ‘mail’ process (pid=3590)

Apr 23 14:34:11 avastd[3591]: warning: can’t set group name to ‘avmail’, Operation not permitted

Apr 23 14:34:11 avastd[3586]: info: started new ‘mail’ process (pid=3591)

Apr 23 14:34:11 avastd[3592]: warning: can’t set group name to ‘avmail’, Operation not permitted

Apr 23 14:34:11 avastd[3586]: info: started new ‘mail’ process (pid=3592)