Possible Duplicate:
problem compiling some ‘math’ using LuaLaTeX
This is a MWE
\documentclass{minimal}
\usepackage{mathptmx}
\usepackage{amsmath}
\usepackage{lualatex-math}
\usepackage{luatextra}
\usepackage{luaotfload}
\usepackage{fontspec}
\setmainfont[Renderer=Basic, Ligatures=TeX,
Scale=1,
ItalicFont={SabonNext LT Italic},
SmallCapsFont={SabonNextLT-RegularSC},
BoldFont={SabonNext LT Bold}
]{SabonNext LT Regular}
%\DeclareSymbolFont{largesymbols}{OMX}{yhex}{m}{n}
\begin{document}
\begin{equation*}
P_{M}\le 4\left( {1-\frac{M_1 +M_2 }{2M}} \right)Q\left[ {\sqrt{\frac{3 \log_{2}M}{\frac{M_1^2 +M_2^2 }{2}-1}\frac{E_{b}}{N_{0}}}} \right]
\end{equation*}
\end{document}
The output has a very big black square. There is not problem with LaTeX (of course, it is necessary to modify the code).
Anyone know whats happening?
