FTP access via proxy server

[R Pradeepa <pradeepa@xxxxxxxxxxxxx>]

when i try to access an ftp site i get the following error

The folder is readonly because the proxy server is not set up to allow 
full access. To move, paste, rename or delete files you should use a 
different proxy server.

Without proxy server i am able to view the ftp sites or add any files to 
that ftp site in IE 6 without any issues.

Please suggest me what ashould be enabled in squid proxy to allow right 
permission to that ftp site


Thanks & Regards
Pradeepa
Sys.Administrator