Problem with FW states

Hi,

   I'm not able to find a solution to this problem:

I've got some devices on the WAN net that need to open telnet connections to a 
telnet server on the LAN net. (OK, don't tell me anything about incoming 
telnet from WAN. At the moment I need to go on this way... )
LAN is bridged with WAN.
I've set up the FW rules and everything works fine.

But...

It often happens that the devices need to be resetted while a telnet 
connection is estabilished. In this case, when the device "reboots" I have to 
wait many minutes to estabilish a telnet connection.

Looking at the FW state logs, I see that every "regular" telnet connection is 
coming from the x port of the device where x is everytime the same.

Every time the device reboots, the new connection, estabilished just waiting 
many minutes, comes from port x+1. On the FWStates log, I see that the old 
state is still active.

If I delete the FW states table before rebooting the device, the new 
connection after reboot is estabilished immediately.
Furthermore, if I connect the device directly on the LAN switch, (excluding 
PFSense filtering), I can reboot the device and have the new connection 
immediately.

I have not been able to analyze the network traffic, but I suppose that the 
device tries everytime to estabilish the telnet connection form port x and 
this is happening

1. A connection is estabilished
2. PFSense keeps an active state DEV:x ==> SRV:23
3. Devicereboot
4. Device tries to estabilish a new connection (Syn from DEV:x to SRV:23)
5. PFSense knows from it's states table that a connection DEV:x ==> SRV:23 is 
already estabilished and drops the new  DEV:x ==> SRV:23 Syn packet
6. After some minutes the device reaches the time-out and tries a new 
connection from port x+1. This new connection works fine.

I've being trying to solve the problem by configuring PFSense
1. inserting a new pass rule  SRV:23 ==> DEV:(x...x+5)
2. not to keep (Firewall: Rules: Edit: State Type: (Advanced) None) the state 
for the "pass" rules
    DEV:(x...x+5) ==> SRV:23
    SRV:23 ==> DEV:(x...x+5)

It doesn't work, even after rebooting PFSense. Furthermore, I can see the the 
state in the States table. So I suppose that the advanced option "State type: 
none" doesn't work.

I also tried to set a state timeout to 10 seconds. The same effect: I can see 
the connection state on the active state table for a long time.

Any suggestion-info-idea?

Thanks in advance to everybody

Odette