asterisk users - Feb 2006 - Trunk calls ring internal analog phone

I am having an issue where outbound external calls.   Calls made using 
an analog line (connected to an FXS) route correctly out the trunk 
(connected to an FXO).  However, when I make a similar outbound call 
using a SIP phone the analog phone connected to the FXS rings.  I was 
having this problem intermittently with a manual asterisk install -- a 
reboot would fix the problem.  I am now giving asterisk@home a spin and 
it happens every time. 

I have included what I think are the relevant portions of the logs.  If 
any more information would help, please let me know and I'll provide them.

When calling from the analog phone (works):
Feb 20 15:41:50 VERBOSE[3773] logger.c:     -- Executing 
GotoIf("Zap/1-1", "0?16") in new stack
Feb 20 15:41:50 DEBUG[3773] pbx.c: Not taking any branch
Feb 20 15:41:50 VERBOSE[3773] logger.c:     -- Executing
Dial("Zap/1-1",
"ZAP/g0/5855961") in new stack
Feb 20 15:41:50 DEBUG[3773] chan_zap.c: Dialing '5855961'
Feb 20 15:41:50 DEBUG[3773] chan_zap.c: Deferring dialing...
Feb 20 15:41:50 VERBOSE[3773] logger.c:     -- Called g0/5855961
Feb 20 15:41:51 DEBUG[3773] chan_zap.c: Exception on 17, channel 4
Feb 20 15:41:51 DEBUG[3773] chan_zap.c: Got event Hook Transition 
Complete(12) on channel 4 (index 0)
Feb 20 15:41:52 DEBUG[3773] chan_zap.c: Exception on 17, channel 4


When calling from the sip phone (doesn't work):
Feb 20 15:43:48 VERBOSE[3810] logger.c:     -- Executing 
GotoIf("SIP/226-b40f", "0?16") in new stack
Feb 20 15:43:48 DEBUG[3810] pbx.c: Not taking any branch
Feb 20 15:43:48 VERBOSE[3810] logger.c:     -- Executing 
Dial("SIP/226-b40f", "ZAP/g0/5855961") in new stack
Feb 20 15:43:48 DEBUG[3810] chan_zap.c: FXO: setup deferred dialstring: 
5855961
Feb 20 15:43:48 VERBOSE[3810] logger.c:     -- Called g0/5855961
Feb 20 15:43:48 VERBOSE[3810] logger.c:     -- Zap/1-1 is ringing
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: Exception on 16, channel 1
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: Got event Ringer Off(11) on 
channel 1 (index 0)
Feb 20 15:43:50 VERBOSE[3810] logger.c:     -- Zap/1-1 is ringing
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: Exception on 16, channel 1
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: Got event Ring/Answered(2) on 
channel 1 (index 0)
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: Enabled echo cancellation on 
channel 1
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: Engaged echo training on channel 1
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: channel 1 answered
Feb 20 15:43:50 DEBUG[3810] chan_zap.c: Sent FXO deferred digit string: 
Tw5855961

Thanks in advance,
Steven