Mysql-Server-5.1 upgrade problem

My System (Linux Debian) got updatet wirth

apt-get update
apt-get upgrade

Everything got upgraded, also my mysql server.
At the upgrade of mysql-server, I got a error message (unfortunately missing. It was at the, when I where asked for mysql admin password).

There was just "Retry" or "cancel". After Retry didnt work, I choosed cancel …

Now the server can´t start anymore

Mysql Error Log:
110502 07:49:48 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
110502 7:49:48 [Note] Plugin 'FEDERATED' is disabled.
/usr/sbin/mysqld: Table 'mysql.plugin' doesn't exist
110502 7:49:48 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
InnoDB: No valid checkpoint found.
InnoDB: If this error appears when you are creating an InnoDB database,
InnoDB: the problem may be that during an earlier attempt you managed
InnoDB: to create the InnoDB data files, but log file creation failed.
InnoDB: If that is the case, please refer to
InnoDB: http://dev.mysql.com/doc/refman/5.1/en/error-creating-innodb.html
110502 7:49:48 [ERROR] Plugin 'InnoDB' init function returned error.
110502 7:49:48 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
110502 7:49:48 [ERROR] /usr/sbin/mysqld: unknown option '–skip-bdb'
110502 7:49:48 [ERROR] Aborting

110502 7:49:48 [Note] /usr/sbin/mysqld: Shutdown complete

110502 07:49:48 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended

with the command "mysql_upgrade" it tells me:
Running 'mysqlcheck' with connection arguments: '–port=3306' '–socket=/var/run/mysqld/mysqld.sock' '–socket=/var/run/mysqld/mysqld.sock'
mysqlcheck: Got error: 2002: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2) when trying to connect
FATAL ERROR: Upgrade failed

Status of the mysql-server-5.1 paket:
Package: mysql-server-5.1
Status: install ok half-configured
Priority: optional
Section: misc
Installed-Size: 13996
Maintainer: Debian MySQL Maintainers
Architecture: i386
Source: mysql-5.1
Version: 5.1.49-3
Replaces: libmysqlclient-dev (<= 5.1.41-1), mysql-server (<< 5.1.49-3), mysql-server-5.0
Provides: mysql-server, mysql-server-5.0, virtual-mysql-server
Depends: mysql-client-5.1 (>= 5.1.49-3), libdbi-perl, perl (>= 5.6), libc6 (>= 2.7), libgcc1 (>= 1:4.1.1), libmysqlclient16 (>= 5.1.21-1), libstdc++6 (>= 4.1.1), zlib1g (>= 1:1.1.4), debconf (>= 0.5) | debconf-2.0, psmisc, passwd, lsb-base (>= 3.0-10), mysql-server-core-5.1 (= 5.1.49-3)
Pre-Depends: mysql-common (>= 5.1.49-3), adduser (>= 3.40), debconf
Recommends: mailx, libhtml-template-perl
Suggests: tinyca
Conflicts: mysql-server (<< 5.1.49-3), mysql-server-4.1
Conffiles:
/etc/logrotate.d/mysql-server 64e209fe34f73fbf10c9479bf30947c4
/etc/mysql/debian-start 4272e4d740c8ae651ac35bbf4d2ed6dc
/etc/mysql/conf.d/mysqld_safe_syslog.cnf 347fa9f3d579ffc06c39bf7e69f4fc6e
/etc/logcheck/ignore.d.workstation/mysql-server-5_1 2d34a7ed83fefc165cd1dfea3a72ccc8
/etc/logcheck/ignore.d.server/mysql-server-5_1 2d34a7ed83fefc165cd1dfea3a72ccc8
/etc/logcheck/ignore.d.paranoid/mysql-server-5_1 6babe46e791059cdd5a26f4f7fec9eca
/etc/init.d/mysql ea6d050ac82ed69d01970f9b95ab9b9d

What I already tried:
apt mirror got updatet

aptitude remove mysql-server-5.1
aptitude install mysql-server-5.1

aptitude update
aptitude full-upgrade

After "aptitude full-upgrade" it shows me (Language: german):

Die folgenden teilweise installierten Pakete werden konfiguriert:
mysql-server-5.1
Es werden keine Pakete installiert, aktualisiert oder entfernt.
0 Pakete aktualisiert, 0 zusätzlich installiert, 0 werden entfernt und 0 nicht aktualisiert.
Muss 0 B an Archiven herunterladen. Nach dem Entpacken werden 0 B zusätzlich belegt sein.
mysql-server-5.1 (5.1.49-3) wird eingerichtet …
Stopping MySQL database server: mysqld.
Starting MySQL database server: mysqld . . . . . . . . . . . . . . failed!
invoke-rc.d: initscript mysql, action "start" failed.
dpkg: Fehler beim Bearbeiten von mysql-server-5.1 (–configure):
Unterprozess installiertes post-installation-Skript gab den Fehlerwert 1 zurück
configured to not write apport reports
Fehler traten auf beim Bearbeiten von:
mysql-server-5.1
E: Sub-process /usr/bin/dpkg returned an error code (1)
Ein Paket konnte nicht installiert werden. Versuche zu lösen:
mysql-server-5.1 (5.1.49-3) wird eingerichtet …
Stopping MySQL database server: mysqld.
Starting MySQL database server: mysqld . . . . . . . . . . . . . . failed!
invoke-rc.d: initscript mysql, action "start" failed.
dpkg: Fehler beim Bearbeiten von mysql-server-5.1 (–configure):
Unterprozess installiertes post-installation-Skript gab den Fehlerwert 1 zurück
Fehler traten auf beim Bearbeiten von:
mysql-server-5.1

Can anyone tell me, what to do now?