mvn install throws error Source option 5 is no longer supported. Use 6 or later.

[ag-123]

when i did an mvn install, mvn throws the error in folder OpenCL4Java:

[ERROR] Source option 5 is no longer supported. Use 6 or later.
[ERROR] Target option 1.5 is no longer supported. Use 1.6 or later.

i tried adding to the pom.xml file:

  <properties>
    <maven.compiler.source>1.6</maven.compiler.source>
    <maven.compiler.target>1.6</maven.compiler.target>
  </properties>

however, i'm not able to get past the error, any clues?