[Asterisk-Users] sip registration fails

[tieum tieum]

I have this problem for 2 days and i dont understand
I am behind a nat
 my sip.conf is:

[general]
port = 5060                 
bindaddr = 0.0.0.0          
context = from-sip       
disallow = all           
allow    = gsm              
allow    = ilbc             
allow    = ulaw             
allow    = alaw
;
;
localnet = 172.27.254.0/255.255.255.0         ; intern network ip address
;localmask = 255.255.255.0   ; 
externip =193.49.116.12       ; my public ip address
;
maxexpirey=180               
defaultexpirey=160            
;
register => 560793:mypasswd at fwd.pulver.com/6002
;
[fwd]
    type=friend
    secret=mypasswd
    username=fayafibun
    host=fwd.pulver.com
    fromdomain=fwd.pulver.com
    insecure=very
    context = from-sip
;
;
;
;
[bombaclaat]                         
  callerid=("bombaclaat" <6009>)     
  type=friend                                
  secret=mypasswd                         
  host=dynamic                        
  auth=md5                           
  defaultip=172.27.254.14             
  context=internal                    
  reinvite=no                         
  canreinvite=no                      
  dtmfmode=rfc2833                     
  disallow=all
  allow=all
  mailbox=bombaclaat                 
  qualify=1000                       
  nat=yes                         
;            
;                                  
[6002]
type=friend
host=dynamic
reinvite=no
canreinvite=no
qualify=1000
dtmfmode=rfc2833
disallow=all
allow=all
;context=internal
context = from-sip
mailbox=6002
;
[6000]
type=friend
host=dynamic
reinvite=no
canreinvite=no
qualify=1000
dtmfmode=rfc2833
disallow=all
allow=all
context=internal
mailbox=6000
;
[bloodclaat]
type=friend
host=dynamic
reinvite=no
canreinvite=no
qualify=1000
dtmfmode=rfc2833
disallow=all
allow=all
context=internal
mailbox=bloodclaat
;
;





my extension.conf
[general]
  static=yes
  writeprotect=no

[globals]
  ;
  ; The name to use on callerid
  ;
  BOMBA=SIP/bombaclaat
  OTRE=SIP/6002
  FWDUSERID=560793
  FWDUSERNAME=fayafibun
  PHONE1=6002
  PHONE1VM=voicemail(6002)
  FWDEXTEND=6002
  ;EVRYONE=${BOMBA}&${OTRE}
  ;
[internal]
  ;
  ; local extensions
  ;
  exten => bombaclaat,1,Dial(SIP/bombaclaat,60) ; call SIP extension
"bombaclaat" for 60 seconds, if extension bombaclaat is called
  exten => bombaclaat,2,Voicemail(ubombaclaat)  ; if we cant connect
to "bombaclaat" or after seconds go to the unavail VM
  exten => bombaclaat,102,Voicemail(bbombaclaat); if busy, go to the busy VM
  exten => 6002,1,Dial(SIP/6002,60)             ; call SIP extension
"bombaclaat" for 60 seconds, if extension bombaclaat is called
  exten => 6002,2,Voicemail(u6002)              ; if we cant connect
to "bombaclaat" or after seconds go to the unavail VM
  exten => 6002,102,Voicemail(b6002)            ; if busy, go to the busy VM
  exten => bloodclaat,1,Dial(SIP/bloodclaat,60)
  exten => bloodclaat,2,Voicemail(ubloodclaat)
  exten => bloodclaat,103,Voicemail(bbloodclaat)
  exten => 6000,1,Dial(SIP/6000,60)
  exten => 6000,2,Voicemail(u6000)
  exten => 6000,103,Voicemail(b6000)
  exten => _[123456789]XXXX,1,NoOp("callfor"${EXTEN})
  exten => _[123456789]XXXX,2,Dial(SIP/${EXTEN},40,tr)
  exten => _[123456789]XXXX,3,Congestion
  exten => 1312605133,1,Dial(${FIPC}/${EXTEN:1},60) ; call SIP
extension "bombaclaat" for 60 seconds, if extensio$
  exten => 1312605133,2,Voicemail(ubombaclaat)  ; if we cant connect
to "bombaclaat" or after seconds go to t$
  exten => bombaclaat,104,Voicemail(bbombaclaat);;
  ;
  ;appeler le 2500 de n importe kel phone pour contacter le voicemail system
  exten => 2500,1,VoicemailMain
  exten => 2500,2,Hangup
  ;
  ;
 ; Voicemail System
  ;
  exten => 123,1,Answer
  exten => 123,2,Playback(tt-weasels)
  exten => 123,3,Voicemail(6002)
  exten => 123,4,Hangup
  ;
  ;
  ;exten => 9999,1,VoiceMailMain(${CALLERIDNUM}) ; extension 9999 is
the VM system,
                                                 ; go directly to callers VM
  ;exten => 9999,2,Hangup
;
;[outbound-internal]
  ;
  ; include local extensions
  ;
;  include => internal
;
;
; include SIP accounts
;
;  include => 6002
;  include => bombaclaat
;  include => 6000
;  include => bloodclaat

[default]
  ;
  ; include from-sip for default. We dont use it, but it might be a good idea
  ;
  ;include => internal
  ;Extension       Description
  ;101             Mark Spencer
  ;102             Wil Meadows
  ;0               Operator
  include => from-sip
  include => fwd-out

[fwd-out]
exten => _7.,1,SetCIDNum(${FWDUSERID})
exten => _7.,2,SetCIDName(${FWDUSERNAME})
exten => _7.,3,Dial(SIP/fwd-outgoin/${EXTEN:1})
exten => _7.,4,Playback(invalid)
exten => _7.,5,Hangup

[from-sip]
exten => ${FWDEXTEN},1,Dial(${PHONE1},30)
exten => ${FWDEXTEN},2,Voicemail(u${PHONE1VM})
exten => ${FWDEXTEN},3,Hangup
exten => ${FWDEXTEN},102,Voicemail(b${PHONE1VM})
exten => ${FWDEXTEN},103,Hangup







I have those errors
Jan 20 11:30:18 NOTICE[98310]: chan_sip.c:4053 sip_reg_timeout:
Registration for '560793 at fwd.pulver.com' timed out, trying again
Jan 20 11:30:24 WARNING[98310]: chan_sip.c:683 retrans_pkt: Maximum
retries exceeded on call
5247c5b244c77b0541f3224372dffab9 at 172.27.254.14 for seqno 112 (Critical
Request)

thanx for help...