Failed to execute goal org.apache.maven.plugins:maven-resources-plugin:2.5:resources (default-resources) on project email: Execution default-resources of goal org.apache.maven.plugins:maven-resources-plugin:2.5:resources failed: A required class was missing while executing org.apache.maven.plugins:maven-resources-plugin:2.5:resources: org/apache/maven/shared/filtering/MavenFilteringException
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realm =    plugin>org.apache.maven.plugins:maven-resources-plugin:2.5
strategy = org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy
urls[0] = file:/home/kamil/.m2/repository/org/apache/maven/plugins/maven-resources-plugin/2.5/maven-resources-plugin-2.5.jar
urls[1] = file:/home/kamil/.m2/repository/org/codehaus/plexus/plexus-utils/1.1/plexus-utils-1.1.jar
Number of foreign imports: 1
import: Entry[import  from realm ClassRealm[maven.api, parent: null]]

-----------------------------------------------------: org.apache.maven.shared.filtering.MavenFilteringException
-> [Help 1]

To see the full stack trace of the errors, re-run Maven with the -e switch.
Re-run Maven using the -X switch to enable full debug logging.

For more information about the errors and possible solutions, please read the following articles:
[Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginContainerException