ulimit warning when restarting

[Will Yardley]

When restarting Dovecot 2.2.10 (via atrpms) on RHEL 6, I get the error:
Warning: fd limit (ulimit -n) is lower than required under max. load (1024 < 4096), because of default_client_limit

# doveconf default_internal_user
default_internal_user = dovecot

Should dovecot print this warning based on $default_internal_user, or
based on root?

As root:
# ulimit -n
1024

As user dovecot:
$ ulimit -n
49152
$ whoami
dovecot

# grep dovecot /etc/security/limits.conf 
dovecot hard locks     49152
dovecot hard nofile    49152
dovecot hard maxlogins 8192
dovecot soft locks     49152
dovecot soft nofile    49152
dovecot soft maxlogins 8192