Ftp (pass mode ) and Iptables

[ludi]

I have a ftp server and run a script of iptables on the server (not a
nat-gateway).  The follow is the script:

iptables -F OUTPUT
iptables -F INPUT
iptables -F FORWARD



iptables -A INPUT -p udp -i eth0 -s 0/0 -d $HOME_ADDR --dport 53 -j ACCEPT
iptables -A INPUT -p tcp -i eth0 -s 0/0 -d $HOME_ADDR --dport 22 -j ACCEPT
iptables -A INPUT -p udp -i eth0 -s 0/0 -d $HOME_ADDR --sport 53 -j ACCEPT
iptables -A INPUT -p tcp -i eth0 -s 0/0 -d $HOME_ADDR --dport 80 -j ACCEPT
iptables -A INPUT -p icmp -i eth0 -s 0/0 -d $HOME_ADDR -m limit
--limit 6/m --limit-burst 6 -j ACCEPT
iptables -A INPUT -i lo -s 0/0 -d 127.0.0.1/32 -j ACCEPT
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -P INPUT DROP


iptables -A OUTPUT -o lo -s 127.0.0.1 -j ACCEPT
iptables -A OUTPUT -o eth0 -s $HOME_ADDR -j ACCEPT
iptables -P OUTPUT DROP
Now, my question is that I can not connect the ftp server with pass
mode until I stop the iptables. I had tried the ip_conntrack_ftp.o
module, but it didnt effect.
Could anyone give me some idea?