Try with -U -up paramters when launching maven.
It should update / download the needed plugins.

On 9/1/06, Sergey Elin < elinsn@gmail.com> wrote:
Here is another build error reproduced on both my boxes (Windows and UNIX) since this morning:

Downloading: http://mirrors.sunsite.dk/maven2/org/apache/maven/plugins/maven-jar
-plugin/2.1/maven-jar-plugin-2.1.pom
[WARNING] Unable to get resource from repository central (http://repo1.maven.org
/maven2)
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Failed to resolve artifact.

GroupId: org.apache.maven.plugins
ArtifactId: maven-jar-plugin
Version: 2.1

Reason: Unable to download the artifact from any repository

  org.apache.maven.plugins:maven-jar-plugin:pom:2.1

from the specified remote repositories:
  central ( http://repo1.maven.org/maven2),
  apache.snapshots (http://people.apache.org/maven-snapshot-repository ),
  codehaus ( http://repository.codehaus.org),
  apache-snapshots (http://people.apache.org/repo/m2-snapshot-repository ),
  codehaus-snapshots ( http://snapshots.repository.codehaus.org)


[INFO] ------------------------------------------------------------------------
[INFO] For more information, run Maven with the -e switch
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 38 seconds
[INFO] Finished at: Fri Sep 01 11:12:08 MSD 2006
[INFO] Final Memory: 25M/46M
[INFO] ------------------------------------------------------------------------

Any suggessions? =(




--
Cheers,
Guillaume Nodet