app_rxfax problem

I have installed asterisk-1.4.17 with spandsp-0.0.4pre16 and app_rxfax/app_txfax.

It seems fax received successfully from Zap channel and saved into .tiff file.

But Zap channel didn’t hangup after finish fax received.

My extensions.conf

exten => s,1,Wait(2)
exten => s,n,NoOp
exten => s,n,NoOp(${CALLERID(all)})
exten => s,n,NoOp(${CALLERID(num)})
exten => s,n,Set(FAXFILE=/tmp/fax_${STRFTIME(${EPOCH},%Y%m%d-%H%M%S)}.tif)
exten => s,n,rxfax(${FAXFILE})
exten => s,n,Hangup
exten => h,1,Hangup
exten => i,1,Hangup
exten => t,1,Hangup

Is there any problem with configuration or app_rxfax?

How can I fix it?