The ebuild references DISTCC_HOSTS, which doesn't seem to exist in the environment. Using "distcc-config --get-hosts" provides the information needed. (untested)
Already have that fixed here in my local version of the ebuild, will commit soon, thanks for the report
This has been fixed now, actually this part isn't necessary anymore (as portage takes care of ccache and distcc without further changes) at all so it has been removed :-)