Maven 3.3+ supports maven.config files in the .mvn folder of a maven project. This file provides support for providing system properties to the JVM at build time. Running Maven builds in Jenkins is doing something to prevent this file from being picked up. Running in Hudson or from the command line on the Jenkins slave works correctly. Running from Jenkins does not.

An example is attached. maven.config should be in .mvn folder at the root of the project.

Incorrect output from Jenkins
[INFO] — exec-maven-plugin:1.4.0:exec (parmValue) @ jenkins-maven-config —
ERROR: Not Set

Correct output should be:
[INFO] — exec-maven-plugin:1.4.0:exec (parmValue) @ jenkins-maven-config —
HelloWorld