Tycho, the new Maven base Eclipse build system, was recently accepted as an Eclipse project. In the latest, 0.12.0 release, the namespace was updated from org.sonatype.tycho to org.eclipse.tycho. This results in lots of changes to your pom.xml files.

I used following script to update; it might save you some time too:

for i in pom.xml */pom.xml
    sed -i -e 's/org.sonatype.tycho/org.eclipse.tycho/g' $i;
    sed -i -e 's/maven-osgi-compiler-plugin/tycho-compiler-plugin/g' $i;
    sed -i -e 's/maven-osgi-packaging-plugin/tycho-packaging-plugin/g' $i;
    sed -i -e 's/maven-osgi-source-plugin/tycho-source-plugin/g' $i;
    sed -i -e 's/maven-osgi-test-plugin/tycho-surefire-plugin/g' $i;
    sed -i -e 's/maven-tycho-plugin/tycho-pomgenerator-plugin/g' $i;
    sed -i -e 's$<tycho-version>0.11.0</tycho-version>$<tycho-version>0.12.0</tycho-version>$g' $i;

If your build is not working because Maven can not download Tycho 0.12.0 from your Maven mirror. Run:

mvn -U clean

This forces a check for updated releases and snapshots on remote repositories and makes sure the update is found.