Could not get m/b working

gistfile1.tex

\documentclass[9pt,a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[english,russian]{babel}
\usepackage{PTSerif}
\usepackage{array}

\begin{document}
\begin{tabular}{| m{1cm} | p{5cm} | b{1cm} |}
\hline
boo &
b dlkf jsdklfjsdlfkjas;l fjsdlk fjasldfj;lskd fjalskjalk jslk jlska jlksa jflskd jfalk jlsk jlksa jlsk jf;asjlaksjl;askj;alskjsalk jlsak &
boo \\
\hline
\end{tabular}
\end{document}