No events are displayed on the calendar displayed by the macro when one of the events has a backslash in the title

Steps to reproduce (using the meeting application that uses a standard calendar macro, with a classname parameter):

• create some meetings
• display them on the calendar by accessing the meetings link "calendar"
• they display properly on the calendar
• create a meeting with a \ in the name

Actual result:

• the calendar is empty, no meeting gets displayed anymore, as long as the part of the calendar that is viewed includes, from the pov of the time filtering, the meeting with \ in the title.