Missing "subtitle" paragraph style in Document class "book (KOMA-script)"

Binary package hint: lyx

Tested with standard lyx install on fully up-to-date Feisty Fawn and Gutsy Gibbon. Not tested on earlier versions of Ubuntu.

1) Create new document.

2) Open the Document-> Settings... dialog box.

3) Change Document class to book (KOMA-Script)

4) Click 'Apply', then 'Close'.

5) Open the Paragraph style selection menu. Paragraph style 'Subtitle' should be displayed, but isn't.

To verify that the above is incorrect, I refer you to the current copy of the English language version of the manual for KOMA-Script which can be found at:

http://www.ctan.org/get/macros/latex/contrib/koma-script/scrguien.pdf

Section 3.3 of this PDF discusses Titles in general. There is example code where the Subtitle type is used in several places. Pasted text examples from my copy of the manual:
===
Table 3.7.: Font defaults for the elements of the title
Element name Default
subject \normalfont\normalcolor\bfseries\Large
title \usekomafont{disposition}
subtitle \usekomafont{title}\large

\titlehead{Titlehead}
\subject{Subject}
\title{Title}
\subtitle{Subtitle}
\author{Author}
\date{Date}
\publishers{Publisher}
\and
\thanks{Footnote}

The Subtitle is set just below the title, in a font determined by the
element subtitle. The default, seen in table 3.7 can be changed with the
help of the commands in section 3.2.1.
Below the Subtitle appears the Author.
===

So far as I can tell, this is the /only/ missing paragraph style from this document class.