asterisk users - Jun 2004 - Problem with incoming calls from FXO

I have  TDM400P , with 1 FXS and 1FXO
I'm tring to forward all incoming calls to a SIP phone
in the context  where all calls from the fxo come i have :
exten => s,1,dial(SIP/phone1000,5)
the phone rings but when i answer the sip phone ( phone1000 ) is connected
but the phone from which i'm ringing still rings.

Here is the log  from asterisk :

*CLI>     -- Starting simple switch on 'Zap/4-1'
Jun 16 12:28:37 NOTICE[213006]: callerid.c:281 callerid_feed: Unknown IE 17
Jun 16 12:28:37 NOTICE[213006]: callerid.c:281 callerid_feed: Unknown IE 48
     -- Executing Dial("Zap/4-1", "SIP/phone1000|5") in new
stack
     -- Called phone1000
     -- SIP/phone1000-c99a is ringing
Jun 16 12:28:38 WARNING[213006]: chan_zap.c:3258 zt_handle_event: 
Ring/Off-hook in strange state 6 on channel 4
     -- SIP/phone1000-c99a answered Zap/4-1
Jun 16 12:28:43 WARNING[213006]: chan_zap.c:3258 zt_handle_event: 
Ring/Off-hook in strange state 6 on channel 4
   == Spawn extension (from-fxo, s, 1) exited non-zero on 'Zap/4-1'
     -- Hungup 'Zap/4-1'