Batmand checks and deliberately blocks users from announcing 0.0.0.0/0 - this could cause the notorious black-hole problem we have experienced in the old days when using OLSR. Also we think it is important that we can explicitly tell a Batman node to use Internet gateway functionality or not.
Default routes in a mesh can be really annoying and break network functionality. If you only have one default gateway in your Batmand network and really know what you are doing you can actually override this check with a simple trick.
As a workaround you can announce two subnetworks 0.0.0.0/1 and 22.214.171.124/1 instead of 0.0.0.0/0.
batmand -a 0.0.0.0/1,126.96.36.199/1 <your interface>