public function addExportDocPosition($exportDocPosition) {
		if($this->getExportDocPosition() === null)
			$this->setExportDocPosition($exportDocPosition);
		else if(is_array($this->getExportDocPosition()))
			$this->exportDocPosition[] = $exportDocPosition;
		else {
			// Convert the first existing entry to an array
			$this->setExportDocPosition(array($this->getExportDocPosition(), $exportDocPosition));
		}
	}