Problem with memoir and biblatex together

Question

For no reason I can understand, I can't compile the following using TexLive 2011:

\documentclass[12pt,a4paper]{memoir}

\usepackage{biblatex}

\bibliography{mnwe-thesis}
\begin{document}

Following Serre\cite{serre_Trees}

\end{document}

with the .bib file mnwe-thesis.bib:

@Book{ serre_Trees,
address = "Berlin",
series = "Springer Monographs in Mathematics",
title = "Trees",
isbn = "3-540-44237-5",
url = "http://www.ams.org/mathscinet-getitem?mr=1954121",
publisher = "{Springer-Verlag}",
author = "{Jean-Pierre} Serre",
year = "2003",
    note = "Translated from the French original by John Stillwell, Corrected 2nd   printing of the 1980 English translation"
}

The error I'm getting is:

.
.
.
(./mnwe.bbl)
Package biblatex Info: Reference section=0 on input line 6.
Package biblatex Info: Reference segment=0 on input line 6.

! Undefined control sequence.
\biburlsetup ->\Urlmuskip 
                      =0mu plus 3mu\relax \mathchardef \UrlBigBreakPenal...
l.13 Following Serre\cite{serre_Trees}

I'm highly surprised since memoir is listed specifically as a compatible package in the biblatex docs.

Edit:

Changing the documentclass to article doesn't help. I also added \listfiles after \begin{document}. The output is here: http://pastebin.com/9dMgNzpz.

Answer 1

The current error is from an outdated url package. Your version is 1999/03/02 ver 1.4, while the most recent on CTAN is 2006/04/12 ver 3.3 which defines \Urlmuskip.