When opening XHTML page, getting error message "Attribute ....space not declared for element 'pre' "

Hi all,

We are trying to use XHTML to author some of our documentation.  The plan is to use FrameMaker to convert the docs to PDF format.

The input file contains the following offending line:

<pre xml:space="preserve">

This should be allowed according to the www.w3.org/1998/xhtml spec.

The actual FM log message is:

Message: Attribute '{http://www.w3.org/XML/1998/namespace}space' is not declared for element 'pre'

Any hints?  I am using Frame Maker 9, by the way.

Thanks,

Frances