lilypond-book bug

[John Williams]

lilypond-book -> Music Fragment options
documents the option: filename="filename"

But the quotes cause an error.  It only works as
  <lilypond filename=filename>
instead of
  <lilypond filename="filename">

Here is the error:

:1:24: error: parse error, expecting `'='':
\renameinput ""filename"
                        "

It does create a filename.ly, but it doesn't seem to use it.
The html output refers to lily-nnnnnn.ly instead of filename.ly:

<a href="lily-1186316085.ly"><img align="center" valign="center"
border="0" src="lily-1186316085.png" alt="[picture of music]"></a>