Problem with passive ftp in IPFW!

[vip 71541]

Good afternoon, everybody. My name is Eugene. I know that not a new issue
... But there is a problem as competently / properly write the rules for
passive ftp in ipfw on a gateway for my LAN. Gateway running Freebsd 8.2p4. For
kernal NAT. Now goes to the local network FTP on such rules here:

00159  0    0 skipto 65000 tcp from 192.168.10.0/24 to any
dst-port21,1024-65535
out xmit em0 keep-state
--
00211 skipto 65000 tcp from any 21,1024-65535 to ${wan_ip}  in recv em0
--
65000  0    0 nat 90 ip from any to any via em0
---
Are there any in ipfw analogue state RELATED in IPTABLES. As an intelligent man
ipfw how to open his information was not found. So, would not open the ports
above 1024 ... But somehow not very good firewall such as leaves and there
is sort of not ...
This kernel is compiled with options such:

# *IPFW*
options IPFIREWALL
options IPFIREWALL_VERBOSE
options IPFIREWALL_VERBOSE=100
options IPFIREWALL_FORWARD
options IPFIREWALL_NAT
options LIBALIAS
options IPDIVERT
options DUMMYNET
options HZ=1000

P.S And plan to add such a state in the next version of freebsd?

Thank you for your attention. I will wait your reply