See the logs:
Jan 4 11:31:35 online imap4-ssl: DEBUG: Connection, ip=[94.254.145.92]
Jan 4 11:31:36 online imap4-ssl: INFO: LOGIN FAILED, user=admin@xxx.pl, ip=[94.254.145.92]
Jan 4 11:31:40 online imap4: INFO: LOGOUT, ip=[94.254.145.92], rcvd=49, sent=302
Jan 4 11:31:40 online imap4: tcpserver: end 12298 status 0
Jan 4 11:31:40 online imap4: tcpserver: status: 0/40
Jan 4 11:31:41 online imap4-ssl: DEBUG: Unexpected SSL connection shutdown.
Jan 4 11:31:41 online imap4-ssl: INFO: LOGOUT, ip=[94.254.145.92], rcvd=45, sent=219
Jan 4 11:31:41 online imap4-ssl: tcpserver: end 12299 status 0
Jan 4 11:31:41 online imap4-ssl: tcpserver: status: 0/40