Code changed in jenkins
User: imod
Path:
src/main/java/org/jvnet/hudson/plugins/m2release/M2ReleaseAction.java
src/main/java/org/jvnet/hudson/plugins/m2release/M2ReleaseBuildWrapper.java
http://jenkins-ci.org/commit/m2release-plugin/c78a508bcb9634c01b582ea7c3791fae86eeded0
Log:
[FIXED JENKINS-12128] expose dryRun flag, release and dev version as env variables

Compare: https://github.com/jenkinsci/m2release-plugin/compare/d302d15...c78a508

Integrated in plugins_m2release #66
[FIXED JENKINS-12128] expose dryRun flag, release and dev version as env variables (Revision c78a508bcb9634c01b582ea7c3791fae86eeded0)

Result = SUCCESS
imod :
Files :

• src/main/java/org/jvnet/hudson/plugins/m2release/M2ReleaseAction.java
• src/main/java/org/jvnet/hudson/plugins/m2release/M2ReleaseBuildWrapper.java

As a convenience to others who may come looking, here are the exposed env vars from the linked code above:
MVN_RELEASE_VERSION
MVN_DEV_VERSION
MVN_ISDRYRUN

It seems like this is no longer working in Jenkins 2.10 + Maven Release Plug-in Plug-in 0.14.0 ?

When I use MVN_RELEASE_VERSION during a release build determined using IS_M2RELEASEBUILD, the value of IS_M2RELEASEBUILD is true but MVN_RELEASE_VERSION is empty string.

Please do not reopen issues that have been working for a long time. See JENKINS-35261

With due respect James, I'm not sure if your reply helped me. I am still unable to print the values stored in these variables.

I am on the Jenkins version 2.42 and with the maven release plugin version as 2.5.3

stage('Maven release') {
 dir('myDir') {
  withMaven(maven: 'Default_Install') {
   sh "mvn -Dmaven.javadoc.skip=true -Dresume=false -B release:prepare && mvn -Dmaven.javadoc.skip=true release:perform"
  }
 }
}
stage('My next step') {
 dir('myDir') {
  sh "env"
   echo "Maven Release Version is $MVN_RELEASE_VERSION"
 }
}

where could I be going wrong?

may I suggest you take this to the users email list as this is not a help forum.