asterisk users - Nov 2004 - Unable to include a context in another context for some unknown reason

I've included the below context in another context for months and
months without any errors.  All of a sudden it's giving me errors. 
The odd thing is that even though it says unable to include, it does
actually include it.  This is what I have.

Now, nowhere else do I have the same extensions under conference under
main menu...

Thanks for any help.

Nov  2 08:27:38 WARNING[1048590]: pbx_config.c:1751 pbx_load_module:
Unable to include context 'conference' in context 'mainmenu'


[conference]
exten => 0001,1,SetVar(CONFID=${UNIQUEID:6:4})
exten => 0001,2,Answer()
exten => 0001,3,Wait(1)
exten => 0001,4,Playback(conf-setup)
exten => 0001,5,Playback(conf-preinfo)
exten => 0001,6,Read(CONFPIN|conf-enterpin|4)
exten => 0001,7,System(/usr/bin/makeconf ${CONFID} ${CONFPIN})
exten => 0001,8,Playback(conf-numberis)
exten => 0001,9,SayDigits(${CONFID})
exten => 0001,10,GotoIf($[${CONFPIN}]?11:100)
exten => 0001,11,Playback(conf-pinis)
exten => 0001,12,SayDigits(${CONFPIN})
exten => 0001,13,Read(repeatvar|conf-repeat|1)
exten => 0001,14,GotoIf($[${repeatvar} = 1]?8:15)
exten => 0001,15,Playback(conf-thankyou)
exten => 0001,16,Hangup()
exten => 0001,100,Playback(conf-nopass)
exten => 0001,101,Goto(conference,0001,13)
exten => *,1,MeetMe()

[mainmenu]
include => conference


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MBM