Since https://github.com/jenkinsci/jenkins/commit/6588f42904ea133b2709750089557e3650bb1910
polling for the clearcase plugin is not working anymore in one of my environments. Any cleartool command fails.

If a build is launched manually, the same commands are called and they perform correctly, so I figured it is an environment override problem.

It turns out the master's environment is overriding slave's environment for polling, which is wrong.