Fax reception and ext-fax


I’m running freepbx and asterisk I have the Schmoozecom.com Fax module. I’ve successfully installed Digium’s Fax For Asterisk.

I added Dadhi fax detection for my DID and set it to send the fax to a virtual extension.

However the extension never accepts the fax. If I look at the dial plan, it says:
exten => s,n,Set(FAX_DEST=from-did-direct^8181^1)

If I change it to the line below, it works.
exten => s,n,Set(FAX_DEST=ext-fax^8181^1)

Is this a bug? Or am I missing a config setting somewhere? Thanks.