asterisk users - May 2004 - I can not register via sip to iptel or sipgate.

I can not register via sip to iptel or sipgate.
i do not unterstand why.. but i am new to asterisk.

Iam behind a susefirewall2 but asterisk even do not register if it shut down.
No answer seems coming back.

thx for help.
nico


here is my config if anybody can help:
-----------------------------------------
[general]
port = 5060?????????????????????; Port to bind to
bindaddr = 190.100.200.1????????????????; Address to bind to
;bindaddr = 0.0.0.0
externip = <extern ip>
nat=1
localnet = 190.100.200.0 ? ? ? ? ; Internal NETWORK address
localmask = 255.255.255.0 ? ? ?; Internal netmask
context = default???????????????; Default for incoming calls
srvlookup = yes?????????; Enable SRV lookups on outbound calls
disallow=all????
allow=gsm???????????????; Disallow all codecs
allow=ulaw
allow=alaw??????????????????????; Allow codecs in order of preference
allow=ilbc

register => <USER>:<PW>@iptel.org/<USER>

[iptel]
type=friend
username=<USER>
secret=<PW>
host=iptel.de
fromuser=<USER>
fromdomain=iptel.de
nat=Yes
context=incomingsipgate
canreinvite=no

The sip debug log:
--------------------
May ?5 13:27:26 WARNING[229391]: chan_sip.c:497 retrans_pkt: Maximum retries 
exceeded on call 5b23ed196b32e7673dbcf54b2c2dbaf0@190.100.200.1 for seqno 139 
(Request)
May ?5 13:27:40 NOTICE[229391]: chan_sip.c:3159 sip_reg_timeout: Registration 
for 'wurz25@195.37.77.101' timed out, trying again
11 headers, 0 lines
Reliably Transmitting:
REGISTER sip:iptel.org SIP/2.0
Via: SIP/2.0/UDP 80.171.10.133:5060;branch=z9hG4bK67698b27
From: <sip:wurz25@iptel.org>;tag=as0ee9b39a
To: <sip:wurz25@iptel.org>
Call-ID: 5b23ed196b32e7673dbcf54b2c2dbaf0@190.100.200.1
CSeq: 140 REGISTER
User-Agent: Asterisk PBX
Expires: 120
Contact: <sip:wurz25@80.171.10.133>
Event: registration
Content-Length: 0

?(no NAT) to 195.37.77.101:5060
Retransmitting #1 (no NAT):
REGISTER sip:iptel.org SIP/2.0
Via: SIP/2.0/UDP 80.171.10.133:5060;branch=z9hG4bK67698b27
From: <sip:wurz25@iptel.org>;tag=as0ee9b39a
To: <sip:wurz25@iptel.org>
Call-ID: 5b23ed196b32e7673dbcf54b2c2dbaf0@190.100.200.1
CSeq: 140 REGISTER
User-Agent: Asterisk PBX
Expires: 120
Contact: <sip:wurz25@80.171.10.133>
Event: registration
Content-Length: 0

X

?to 195.37.77.101:5060
Retransmitting #2 (no NAT):
REGISTER sip:iptel.org SIP/2.0
Via: SIP/2.0/UDP 80.171.10.133:5060;branch=z9hG4bK67698b27
From: <sip:wurz25@iptel.org>;tag=as0ee9b39a
To: <sip:wurz25@iptel.org>
Call-ID: 5b23ed196b32e7673dbcf54b2c2dbaf0@190.100.200.1
CSeq: 140 REGISTER
User-Agent: Asterisk PBX
Expires: 120
Contact: <sip:wurz25@80.171.10.133>
Event: registration
Content-Length: 0