How to prevent Scala pretty printer to remove CDATA?

I've used Scala xml PrettyPrinter library to format xml files. It removes the tags content that has CDATA section. How can I prevent PrettyPrinter to remove CDATA?

this is the code :

val printer = new scala.xml.PrettyPrinter(80, 2)
printer.format(XML.loadString(input))

it converts <textFieldExpression><![CDATA[something]]></textFieldExpression> to <textFieldExpression>something</textFieldExpression>