Lesbare URL´s

Hallo Drupalgemeinde,
meine Php Kenntnisse sind leider sehr begrenzt daher brauche ich dringend eure Hilfe.
Bei der Aktivierung der Lesbaren URL´s funktioniert alles wunderbar, außer der Menüpunkt "Verwalten".
Bei ihm bekomme ich die Fehlermeldung: "Seite wurde nicht gefunden".
Der Server ist ein Apache 2.2.10 (Unix) mit der PHP Version 5.2.5.
Hier noch die .htaccess -Datei. Es ist die Standard Datei, bei der ich auch nichts verändert habe.
Welche Änderungen muss ich vornehmen damit es funktioniert?
Danke im Voraus!

#
# Apache/PHP/Drupal settings:
#

# Protect files and directories from prying eyes.

Order allow,deny

# Don't show directory listings for URLs which map to a directory.
Options -Indexes

# Follow symbolic links in this directory.
Options +FollowSymLinks

# Customized error messages.
ErrorDocument 404 /index.php

# Set the default handler.
DirectoryIndex index.php

# Override PHP settings. More in sites/default/settings.php
# but the following cannot be changed at runtime.

# PHP 4, Apache 1.

php_value magic_quotes_gpc 0
php_value register_globals 0
php_value session.auto_start 0
php_value mbstring.http_input pass
php_value mbstring.http_output pass
php_value mbstring.encoding_translation 0

# PHP 4, Apache 2.

php_value magic_quotes_gpc 0
php_value register_globals 0
php_value session.auto_start 0
php_value mbstring.http_input pass
php_value mbstring.http_output pass
php_value mbstring.encoding_translation 0

# PHP 5, Apache 1 and 2.

php_value magic_quotes_gpc 0
php_value register_globals 0
php_value session.auto_start 0
php_value mbstring.http_input pass
php_value mbstring.http_output pass
php_value mbstring.encoding_translation 0

# Requires mod_expires to be enabled.

# Enable expirations.
ExpiresActive On
# Cache all files for 2 weeks after access (A).
ExpiresDefault A1209600
# Do not cache dynamically generated pages.
ExpiresByType text/html A1

# Various rewrite rules.

RewriteEngine on

# If your site can be accessed both with and without the 'www.' prefix, you
# can use one of the following settings to redirect users to your preferred
# URL, either WITH or WITHOUT the 'www.' prefix. Choose ONLY one option:
#
# To redirect all users to access the site WITH the 'www.' prefix,
# (http://example.com/... will be redirected to http://www.example.com/...)
# adapt and uncomment the following:
# RewriteCond %{HTTP_HOST} ^example\.com$ [NC]
# RewriteRule ^(.*)$ http://www.example.com/$1 [L,R=301]
#
# To redirect all users to access the site WITHOUT the 'www.' prefix,
# (http://www.example.com/... will be redirected to http://example.com/...)
# uncomment and adapt the following:
# RewriteCond %{HTTP_HOST} ^www\.example\.com$ [NC]
# RewriteRule ^(.*)$ http://example.com/$1 [L,R=301]

# Modify the RewriteBase if you are using Drupal in a subdirectory or in a
# VirtualDocumentRoot and the rewrite rules are not working properly.
# For example if your site is at http://example.com/drupal uncomment and
# modify the following line:
# RewriteBase /drupal
#
# If your site is running in a VirtualDocumentRoot at http://example.com/,
# uncomment the following line:
# RewriteBase /

# Rewrite old-style URLs of the form 'node.php?id=x'.
#RewriteCond %{REQUEST_FILENAME} !-f
#RewriteCond %{REQUEST_FILENAME} !-d
#RewriteCond %{QUERY_STRING} ^id=([^&]+)$
#RewriteRule node.php index.php?q=node/view/%1 [L]

# Rewrite old-style URLs of the form 'module.php?mod=x'.
#RewriteCond %{REQUEST_FILENAME} !-f
#RewriteCond %{REQUEST_FILENAME} !-d
#RewriteCond %{QUERY_STRING} ^mod=([^&]+)$
#RewriteRule module.php index.php?q=%1 [L]

# Rewrite current-style URLs of the form 'index.php?q=x'.
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?q=$1 [L,QSA]

# $Id: .htaccess,v 1.81.2.4 2008/01/22 09:01:39 drumm Exp $