Project import from csv containing umlautes creates � characters

When importing csv files containing umlautes using the project importer, the characters with umlautes are being replaced by � characters. This already shows up in the 3rd step when going through the import wizard.

This has been pointed out by an OnDemand customer, confirmed by testing it on an ondemand instance on jira-dev, however on jira standalone 5.2.4 it all seemed to be functioning normally.