"Bamboo Plan Summary Chart" gadget crash on machines without X11

Steps:
1. setup GNU/Linux box without X11
2. install Bamboo on it
3. create application link between Jira and Bamboo
4. add Bamboo Plan Summary Chart gadget to Jira dashboard
5. error occurs

Asking for /bamboo/rest/api/latest/chart/planSummary.json returns HTTP 500 instead JSON.

Solution:
Add this line
CATALINA_OPTS="-Djava.awt.headless=true"
to file bin/catalina.sh or this line
System.setProperty("java.awt.headless", "true");
somewhere inside Bamboo source code (not sure - I'm not Java programmer).