[asterisk-r2] mfcr2 doesnt show any channels

[Gomespereira]

Hello to all
every time I do "mfcr2 show channels"  I only see one line like this:

*CLI> mfcr2 show channels
Chan Variant Max ANI Max DNIS ANI First Immediate Accept tx CAS Rx CAS
*CLI>


here is my chan_dahdi: ---------------------------------
[channels]
language=en
context=incomingr2
signalling=mfcr2
switchtype=national
mfcr2_variant=mx (Im connecting to Angola Telecom,
		; is this the correct variant for Angola?)

;if I uncoment this line asterisk doesnt start
;channel => 1-15,17-31


and my /etc/dahdi/system.conf ----------------------------
span=1,1,0,cas,hdb3
cas=1-15:1101
dchan=16
cas=17-31:1101



What could be missing?
What other commands can I use for debug?
Thanks
Regards
Joao Pereira