Found out how to do it. :-)
When using webservice databinding, it needs to be done client-side with some jQuery templating engine, eg. like this:
functionwsOnSchedulerDataBound(scheduler) { $(".rsApt").each(function() { varl_oAppointment = scheduler.getAppointmentFromDomElement(this); varl_aAttr = l_oAppointment.get_attributes(); varbgColor = l_aAttr.getAttribute('BgColor'); l_oAppointment.set_backColor(bgColor); }); $(".rsAptDelete").each(function() { varl_oAppointment = scheduler.getAppointmentFromDomElement(this); varl_aAttr = l_oAppointment.get_attributes(); // creating an object containing the data that should be applied on the template varl_aValues = { NumberOfPlaces: l_aAttr.getAttribute('NumberOfPlaces'), TaskPoints: l_aAttr.getAttribute('TaskPoints'), AgeMin: l_aAttr.getAttribute('AgeMin'), AgeMax: l_aAttr.getAttribute('AgeMax'), Gender: l_aAttr.getAttribute('Gender') }; // instantiate the template, populate it and insert before the delete handler (".rsAptDelete") $('<div></div>').loadTemplate("#tmplAppointmentData", l_aValues).insertBefore(this); });};