How to specify different authority to different user in VSFTPD
 

Hi all ,I has just installed the vsftpd and it works perfectlly,
but I must specify different authority to different user when they access a same folder.
Example:
user operation

hello1 all(upload/download/rename/delete...)
hello2 upload/download
hellp3 download

How can I set up to perform these in vsftpd&ubuntu5.10?
(Now I'm using vsftpd,maybe I have to change another ftp server)