le plugin introuvable

Bonjour,

J'utilise les plugins :
maven-surefire-report-plugin
org.codehaus.mojo
maven-checkstyle-plugin
taglist-maven-plugin

voici un extrait de mon pom :

Citation:

<reporting>
<plugins>

<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-report-plugin</artifactId>
<configuration>
<showSuccess>false</showSuccess>
</configuration>
</plugin>

<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>cobertura-maven-plugin</artifactId>
</plugin>

<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
<configuration>
<configLocation>${basedir}\src\site\checkstyle.xml</configLocation>
</configuration>
</plugin>

<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>taglist-maven-plugin</artifactId>
<configuration>
<tags>
<tag>TODO</tag>
<tag>@todo</tag>
<tag>FIXME</tag>
<tag>XXX</tag>
</tags>
</configuration>
</plugin>

</plugins>
</reporting>

Quand je lance mvn site j'obtient ça :

Citation:

C:\Applications\Circe\souldmo_circe_dev_snap\legacy>mvn site
[INFO] Scanning for projects...
[INFO] Reactor build order:
[INFO] Circe Root
[INFO] circe lib
[INFO] circe utils
[INFO] circe
[INFO] circe mdi
[INFO] ----------------------------------------------------------------------------
[INFO] Building Circe Root
[INFO] task-segment: [site]
[INFO] ----------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] The plugin 'org.apache.maven.plugins:maven-surefire-report-plugin' does not exist or no valid version could be found
[INFO] ------------------------------------------------------------------------
[INFO] For more information, run Maven with the -e switch
[INFO] ------------------------------------------------------------------------
[INFO] Total time: < 1 second
[INFO] Finished at: Fri Sep 08 17:47:30 CEST 2006
[INFO] Final Memory: 2M/4M
[INFO] ------------------------------------------------------------------------

Le plugin n'existe pas alorsque c'est un plugin de maven ?

Merci d'avance