Maven javac: invalid target release: 1.7

When I try to compile my maven project by running "mvn package", I get the following error

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.3.2:compile (default-compile) on project onix-generator: Compilation failure
[ERROR] Failure executing javac, but could not parse the error:
[ERROR] javac: invalid target release: 1.7
[ERROR] Usage: javac
[ERROR] use -help for a list of possible options

1) Check your Java version:

java -version

java version "1.7.0_09"
Java(TM) SE Runtime Environment (build 1.7.0_09-b05)
Java HotSpot(TM) 64-Bit Server VM (build 23.5-b02, mixed mode) 

2) Check javac version:

javac -version

javac 1.7.0_09

3) Check $JAVA_HOME

Make sure it points to the java bin directory.