NPE in Maven jobs when custom workspace location is configured

java.lang.RuntimeException: Unable to determine Maven version
	at org.jfrog.hudson.maven3.extractor.MavenExtractorEnvironment.isMavenVersionValid(MavenExtractorEnvironment.java:135)
	at org.jfrog.hudson.maven3.extractor.MavenExtractorEnvironment.buildEnvVars(MavenExtractorEnvironment.java:88)
	at hudson.model.AbstractBuild.getEnvironment(AbstractBuild.java:804)
	at hudson.maven.AbstractMavenBuild.getEnvironment(AbstractMavenBuild.java:59)
	at hudson.maven.MavenModuleSetBuild.getEnvironment(MavenModuleSetBuild.java:165)
	at hudson.model.AbstractBuild$AbstractRunner.decideWorkspace(AbstractBuild.java:419)
	at hudson.model.AbstractBuild$AbstractRunner.run(AbstractBuild.java:436)
	at hudson.model.Run.run(Run.java:1376)
	at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:479)
	at hudson.model.ResourceController.execute(ResourceController.java:88)
	at hudson.model.Executor.run(Executor.java:230)
Caused by: java.lang.NullPointerException
	at org.jfrog.hudson.util.MavenVersionHelper.isAtLeast(MavenVersionHelper.java:103)
	at org.jfrog.hudson.util.MavenVersionHelper.isAtLeastVersion(MavenVersionHelper.java:75)
	at org.jfrog.hudson.util.MavenVersionHelper.isAtLeastResolutionCapableVersion(MavenVersionHelper.java:65)
	at org.jfrog.hudson.maven3.extractor.MavenExtractorEnvironment.isMavenVersionValid(MavenExtractorEnvironment.java:133)	..