Output encoding us-ascii and character references

I'm using Saxon 9.1.0.7J with Java 1.6.0_17 64-bit and with or without Xerces
2.9.1 under Vista and have an XSL 2.0 transform with:

<xsl:output method="text" media-type="text/plain" encoding="us-ascii" />

when I run the transform I get the following error:

Output character not available in this encoding (decimal 697)

I thought that when you specified us-ascii as an output encoding and a
character was outside the encoding, then the XSL processor was suppose to
render a character reference or was I dreaming?


Andy.