In order to switch net-im/prosody using dev-lua/lua-bit32 instead of dev-lua/LuaBitOp, dev-lua/lua-bit32 needs ~arm keyword, since net-im/prosody has it. @sam: As spoken on IRC, please test, if keywording is possible :-) Thanks!
https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=40c1d8ffaa7fb77a67d9f02cdd21c01bfaf76de4
Unable to check for sanity: > no match for package: dev-lua/lua-bit32-5.3.5