build.log it says but a bit truncated

dev-ruby:activesupport-2.3.5:20100118-003905.log (text/plain), 1.49 KB, created by David J Cozatt on 2010-01-21 23:18:24 UTC

>>> Unpacking source...
>>> Source unpacked in /var/tmp/portage/dev-ruby/activesupport-2.3.5/work
>>> Compiling source in /var/tmp/portage/dev-ruby/activesupport-2.3.5/work ...
>>> Source compiled.
>>> Test phase [not enabled]: dev-ruby/activesupport-2.3.5

>>> Install activesupport-2.3.5 into /var/tmp/portage/dev-ruby/activesupport-2.3.5/image/ category dev-ruby
 [32;01m*[0m Installing for ruby18...
ERROR:  While executing gem ... (OptionParser::InvalidOption)
    invalid option: --sandbox-fix
 [31;01m*[0m 
 [31;01m*[0m ERROR: dev-ruby/activesupport-2.3.5 failed.
 [31;01m*[0m Call stack:
 [31;01m*[0m               ebuild.sh, line   49:  Called src_install
 [31;01m*[0m             environment, line 2513:  Called gems_src_install
 [31;01m*[0m             environment, line 1399:  Called die
 [31;01m*[0m The specific snippet of code:
 [31;01m*[0m           /usr/bin/${ruby_version} /usr/bin/gem install ${GEM_SRC} --version ${PV} ${myconf} --local --install-dir "${D}/${GEMSDIR}" --sandbox-fix --no-user-install || die "gem (>=1.3.0) install failed";
 [31;01m*[0m  The die message:
 [31;01m*[0m   gem (>=1.3.0) install failed
 [31;01m*[0m 
 [31;01m*[0m If you need support, post the topmost build error, and the call stack if relevant.
 [31;01m*[0m A complete build log is located at '/var/log/portage/dev-ruby:activesupport-2.3.5:20100118-003905.log'.
 [31;01m*[0m The ebuild environment file is located at '/var/tmp/portage/dev-ruby/activesupport-2.3.5/temp/environment'.
 [31;01m*[0m