Filtering vcalendar dates with File_IMC

Hi there i was wondering how its possible to convert the parsed vcalendar data array back to xml to somehow filter vevents by a date range to publish to a server ? Im looking into some date filtering options to a class im building. Also ive noticed that Mozilla Sunbird doesnt export the calendar name which is needed to identify who is publishing what as its for events listings. I could try and use the logged in user i suppose.