Indeed 1.288 seems to be missing from

http://maven.glassfish.org/content/groups/public/org/jvnet/hudson/main/hudson-core/

yet plugins/pom.xml requests it. So:

[INFO] Building Hudson Mercurial plugin
[INFO] task-segment: [install]
[INFO] ------------------------------------------------------------------------
[INFO] [enforcer:display-info

]
[INFO] Maven Version: 2.0.9
[INFO] JDK Version: 1.6.0_11 normalized as: 1.6.0-11
[INFO] OS Info: Arch: i386 Family: unix Name: linux Version: 2.6.27-11-generic
[INFO] [localizer:generate

]
[INFO] [resources:resources]
[INFO] Using default encoding to copy filtered resources.
Downloading:
http://maven.glassfish.org/content/groups/public//org/jvnet/hudson/main/hudson-war/1.288/hudson-war-1.288.pom
Downloading:
http://repo1.maven.org/maven2/org/jvnet/hudson/main/hudson-war/1.288/hudson-war-1.288.pom
Downloading:
http://maven.glassfish.org/content/groups/public//org/jvnet/hudson/main/hudson-core/1.288/hudson-core-1.288.pom
Downloading:
http://repo1.maven.org/maven2/org/jvnet/hudson/main/hudson-core/1.288/hudson-core-1.288.pom
Downloading:
http://maven.glassfish.org/content/groups/public//org/jvnet/hudson/main/hudson-test-harness/1.288/hudson-test-harness-1.288.pom
Downloading:
http://repo1.maven.org/maven2/org/jvnet/hudson/main/hudson-test-harness/1.288/hudson-test-harness-1.288.pom
Downloading:
http://maven.glassfish.org/content/groups/public//org/jvnet/hudson/main/hudson-core/1.288/hudson-core-1.288.jar
Downloading:
http://repo1.maven.org/maven2/org/jvnet/hudson/main/hudson-core/1.288/hudson-core-1.288.jar
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Failed to resolve artifact.

Missing:
----------
1) org.jvnet.hudson.main:hudson-core:jar:1.288
.....