dunecontrol: extremly unhelpful error when dependencies are separated by ","

When separating dependencies in the Depends:-line in dune.module by a comma (,), The error message becomes something like this:

joe@paranoia:~/linuxhome/Projekte/pra-wire-sose-2016/Dune$ ./dunecontrol --opts=debug.opts all
----- using default flags $CONFIGURE_FLAGS from /home/joe/linuxhome/Projekte/pra-wire-sose-2016/Dune/debug.opts -----
ERROR: invalid module name  (dependency of dune_cppbasics)
Execution of dunecontrol terminated due to errors!

The code in dunemodules.lib looks like it is meant to support this, but seems top be buggy.

This happens the the 2.4 branch, no idea about master.