Dear all,
I have configured a proxy server on my Linux Machine (Redhat 5).Every thing is working except ftp.My local clients are Windows XP and the tool we are using is WS_FTP Professional.Other Service are working properly http,https etc.But i can connect properly from the squid machine to the remote FTP Server but not from our windows clients.My Squid configuration file is posted below.

http_port 3128
acl all src 0.0.0.0/0.0.0.0
acl manager proto cache_object
acl localhost src 127.0.0.1/255.255.255.255
acl to_localhost dst 127.0.0.0/8
acl SSL_ports port 443
acl Safe_ports port 80 # http
acl Safe_ports port 21 # ftp
acl Safe_ports port 443 # https
acl Safe_ports port 70 # gopher
acl Safe_ports port 210 # wais
acl Safe_ports port 1025-65535 # unregistered ports
acl Safe_ports port 280 # http-mgmt
acl Safe_ports port 488 # gss-http
acl Safe_ports port 591 # filemaker
acl Safe_ports port 777 # multiling http
acl CONNECT method CONNECT
acl ftp proto FTP

acl our_networks src 91.0.0.0/24
http_access allow our_networks

# And finally deny all other access to this proxy
http_access allow localhost
always_direct allow ftp
http_access deny all

Any help will be appreciated.