MNG-5538 introduced CLASSWORLDS_JAR, but the issue was dropped due to reproducibility, however mvn.cmd has also a CLASSWORLDS_JAR variable. Both scripts shall behave the same way.
Reapply commits from MNG-5538 as this issue.
mvn start script causes cygwin warning
Fixed with 4337d18af65df8d3221bdd1e393f13c5f4db9054.
SUCCESS: Integrated in Jenkins build maven-3.x #1523 (See https://builds.apache.org/job/maven-3.x/1523/)
MNG-6163 Introduce CLASSWORLDS_JAR in shell startup scripts (michaelo: http://git-wip-us.apache.org/repos/asf/?p=maven.git&a=commit&h=4337d18af65df8d3221bdd1e393f13c5f4db9054)