We were told that we should use the 'minimal' USE flag to build mysql client programs only without installing the server. This seems to disable LOAD DATA INFILE in our Perl programs though: DBD::mysql::st execute failed: The used command is not allowed with this MySQL version at /usr/lib/perl5/vendor_perl/5.8.8/DBIx/ContextualFetch.pm line 52. Removing the minimal USE flag and rebuilding re-enables the feature. Suggestion: add a 'clientonly' flag and don't conflate minimal and client-only (look at the description of the minimal flag, and you'd never guess that this builds client libraries only, you'd think it's a minimal server).
I've re-added the "--enable-local-infile" option when building. There is now a use.local.desc for dev-db/mysql* that explain a bit better what it does for mysql. No using a clientonly flag is not an option as it has been discussed often before. If upstream split out a client only package, instead to force a full download and as 5.0.30 a full /build/ of the server, that is discarded at the end than there would be a different ebuild only for that.
