(4.2.0) Character set encoding

If you are working with non-Latin1 character sets (for example, Cyrillic, Czech, Hungarian, etc.) it is recommended to run your Jira system in UTF-8 across the database, application server and web application. 

See the Atlassian Knowledge Base article Troubleshoot character display issues in Jira Server for details and how to change Jira's startup options.