vsftp 500 OOPS: could not bind listening IPv4 socket

mzr525

centos 5  vsftp -vsftpd-2.0.5  

more builddefs.h
#ifndef VSF_BUILDDEFS_H
#define VSF_BUILDDEFS_H

#define VSF_BUILD_TCPWRAPPERS
#undef VSF_BUILD_PAM
#undef VSF_BUILD_SSL

#endif /* VSF_BUILDDEFS_H */

make
make install

vi /etc/vsftpd.conf

anonymous_enable=NO
local_enable=YES
write_enable=YES
local_umask=022
listen=YES
listen_port=21211
tcp_wrappers=YES

more /etc/xinetd.d/vsftpd   
disable                 = yes

[root@mzr vsftpd-2.0.5]# /usr/local/sbin/vsftpd &
[3] 3781
[root@mzr vsftpd-2.0.5]# 500 OOPS: could not bind listening IPv4 socket

但是我可以用系统用户成功登陆，这是为什么，我该怎么解决？
Name (127.0.0.1:root): mzr
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp>