DHX Calendar Cell

When the number of rows on a grid reaches the bottom of the page and I attempt to edit a cell with a calendar in it the calendar disappears off the edge of the screen and cannot be editied or accessed. how can i prevent this from occuring.

See attached image for reference

You may change the position of the calendar pop-up the following way:

mygrid.attachEvent("onCalendarShow", function(myCal,rId,colInd){ var cell = this.editor.cell; var pos = this.getPosition(cell); myCal.setPosition(pos[0],pos[1]-217) })