The app-text/texlive-2011.ebuild depends on dev-tex/mh. However, a newer version of mh is installed by texlive-latexextra. Installing the mh version in dev-tex will brake stuff such as the \sfrac command together with sunitx. If dev-tex/mh is installed with all texlive 2011 packages the following error will occur if fractions are used "Illegal unit of measure (pt inserted)". This error does not occur if dev-tex/mh is uninstalled and the bundled version of texlive-latexextra is used. Reproducible: Always Steps to Reproduce: 1. Update to texlive-2011 2. Use \sfrac together with sunitx 3. Illegal unit of measure (pt inserted) is reported by latex Expected Results: latex compiles fine dev-tex/mh is an older version then the one bundled with texlive-latexextra
bumped dev-tex/mh and the min req version for texlive , this should fix your problem, thanks for the report!