If you look closely at the documentation for the ftp daemon, you will find that you cannot access ftp the way you are trying to:
From the QNX documentation at ($QNX_INSTALL_PATH)/target/qnx6/usr/help/product/neutrino/utilities/f/ftpd.html
and under the heading “User authorization”
The ftpd daemon authenticates users according to these rules:
1. The username must be in the password database /etc/passwd and must not have a null password. The client must provide a password before any file operations may be performed.
2. The username must not appear in the /etc/ftpusers file, which contains a list of users who aren't allowed to use ftp. One username is listed per line. If this file is missing, no user on the local system may access ftp.
So… first of all, give your root user a password and check then that the /etc/ftpusers exists and try again.
Better still… grab scp/ssh and use a secure approach.