Summary:
When run from a Windows client, using either PowerShell or the traditional cmd.exe command prompt, use of the groovysh CLI command produces unexpected characters and formatting in the output. This can be seen when connecting to both Windows and Linux Jenkins servers.

Steps to recreate:

1. Install and launch the latest weekly of Jenkins on either a Linux or a Windows server.
2. Download the most up to date version of jenkins-cli.war from this same Jenkins.
3. Run java -jar jenkins-cli.jar -s http://1.2.3.4:8080/ -ssh -user admin groovysh from a Windows system.
4. Although the command seems to work, its output is badly formatted. Screen shots immediately below.

PowerShell:

cmd.exe:

Everything is formatted correctly when run from a Linux box. This is the same command, pointed at the same Jenkins: