Claiming the task 'Handle vacation request' as user 'Kermit' in Konqueror 4.3.2, fails with the message 'Failed to process template org/activiti/rest/api/tasks/task.get.json.ftl'. The same happens during submission of task forms (after claiming them via Firefox).
The positioning of header images in Activiti Probe and Activiti Explorer looks also slightly wrong in Konqueror.
I've been running Activiti 5.0.alpha2.