Problem css in ie7, fine in ff

[Maikel]

I am trying to build a calendar, in Firefox everything works perfect, in ie7 it looks asif it doesn't get its css styles.

I used a extend on the ContentPanel where i build it.

Something in the like of this:

dh.append('Ext.ux.PlannerPanel', calheader, true); //plannerdaybar
dh.append('planner_top', {tag: 'div', id: 'planner_days_content'}, true);
dh.append('planner_days_content', calspacer, true); //spacer plannerdaybar
dh.append('planner_days_content', caldayblock, true); //dayblock in headercontent

var plannerwidth = Ext.fly('planner_dayHeader');

plannerwidth = plannerwidth.getWidth();
var daywidth = (plannerwidth/this.days)-2;

Ext.util.CSS.updateRule(".plannerdays div", "width", daywidth + "px");
Ext.util.CSS.updateRule(".plannerevents div", "width", daywidth + "px");
Ext.util.CSS.updateRule(".planner_appointments_day", "width", daywidth + "px");

I already checked my code for extra comma's but can't seem to find any.

Does anyone have a idea maybe where to look?