buildbot exception in on ofbiz-trunk-rat

[buildbot]

The Buildbot has detected a build exception on builder ofbiz-trunk-rat while 
building . Full details are available at:
    https://ci.apache.org/builders/ofbiz-trunk-rat/builds/986

Buildbot URL: https://ci.apache.org/

Buildslave for this Build: lares_ubuntu

Build Reason: The AnyBranchScheduler scheduler named 'on-ofbiz-commit' 
triggered this build
Build Source Stamp: [branch ofbiz/trunk] 1762080
Blamelist: jacopoc,jleroux

BUILD FAILED: exception shell

Sincerely,
 -The Buildbot