NAT Problem

["Manfred F." <vipi@fastflowsrl.com>]

Hi,
I have a problem with to connect from firewall/NAT:
The sistuation is:

Kerberos server in the internal net and i use NAT for external 
connection (usual network 192.168.1.X -> REAL IP)
I use NAT also in DMZ.( 192.168.2.X )
The comunication btw DMZ and internal net 
are with Real IP (i know double NAT :-( )

When i telnet from DMZ to DMZ no problem 
(i get the ticket and so on..)
When i try to connect from internal net to DMZ 

kinit --no-address
telnet -l manfred panoramix.aigo.it
Trying 151.36.98.141...
Connected to panoramix.aigo.it (151.36.98.141).
Escape character is '^]'.
[ Kerberos V5 refuses authentication because Read req failed: Key table entry not found ]
[ Kerberos V5 refuses authentication because Read req failed: Key table entry not found ]
telnetd: Authorization failed.
Connection closed by foreign host.

klist -a
Ticket cache: FILE:/tmp/krb5cc_500
Default principal: manfred@AIGO.INTRA

Valid starting     Expires            Service principal
09/02/01 18:57:27  09/03/01 01:38:40  krbtgt/AIGO.INTRA@AIGO.INTRA
	Addresses: (none)
09/02/01 18:58:01  09/03/01 01:38:40  host/panoramix.aigo.it@AIGO.INTRA
	Addresses: (none)

Some data from DMZ to DMZ 
kinit  --no-address 
klist -a
Ticket cache: FILE:/tmp/krb5cc_500
Default principal: manfred@AIGO.INTRA

Valid starting     Expires            Service principal
09/02/01 19:03:18  09/03/01 01:43:15  krbtgt/AIGO.INTRA@AIGO.INTRA
	Addresses: (none)
09/02/01 19:04:06  09/03/01 01:43:15  host/panoramix.aigo.it@AIGO.INTRA
	Addresses: (none)

There is something in krb5.conf to do ? 
(already set in the krb5.con extra_address real_ip and nat ip .. )

Can someone help me ? 

Thank you ...

bye manfred