Liboperaw-0.0.8 fails because not finding bzero like version 0.0.5, see bug 243200. But including cstring does not work on solaris. It seems like it must be strings.h, thats also what man bzero says on solaris. Another problem is the use of get_current_dir_name in testsuite/testsuite.cpp. It's already reported upstream an form there also the patch comes.
Created attachment 206307 [details, diff] includes strings.h
Created attachment 206309 [details, diff] fixes the testsuite
Created attachment 206310 [details, diff] ebuild which includes both patches
note: patches go in src_prepare in an EAPI=2 ebuild. patches applied, thanks