[XeTeX] Polyglossia "broken"?

[Arash Zeini]

Hello,

I updated my vanilla TexLive 2011 installation two days ago and have since 
been unable to compile my document correctly. Nothing has changed in my 
document but I now receive 181 error messages, most of which relate to 
polyglossia. Here are some examples:

Package polyglossia Warning: \english at font@rm is not defined on input line 27.

! Extra \fi.
\inlineextras at german ...ds \german at shorthands \fi 
                                                  
l.183 ...e (`\textgerman{individuelle Lebensdauer}
                                                  ').\footnote{For an 
altern...

My editor opens up this section of polyglossia.sty:

%% ensure localization of \markright and \markboth commands
%%% THIS IS NOW DISABLED BY DEFAULT
\define at boolkey{polyglossia}[xpg@]{localmarks}[false]{%
   \ifbool{xpg at localmarks}{%
      \xpg at info{Option:~ localmarks}%
...

And this minimal example successfully reproduces the errors:

\documentclass[a4paper,12pt,oneside]{memoir}
\usepackage{fontspec}
\setmainfont[Mapping=tex-text]{Linux Libertine O}
\usepackage{polyglossia}
\setdefaultlanguage[variant=british]{english}
\setotherlanguages{german, french}

\begin{document}
\begin{quote}
	\textgerman{Die Wahrheit wird, auch hier, in der Mitte der Gegensätze 
liegen \dots}
\end{quote}
\end{document}

Does anyone happen to know what might cause these errors?

Best wishes,
Arash