Error with Emacspeak 8.0, Emacs 20.3 and W3 4.0 beta 23

[Jason White <jasonw@xxxxxxxxxxx>]

I have just installed Emacs 20.3 and encountered the following problem
when running it with Emacspeak 8.0 and W3 4.0 beta 23. When reading
certain parts of an HTML document, usually somewhere in the midst of the
text, though I have been unable to isolate the exact circumstances in
which this occurs, Emacs fails to read the current line and signals an
error. Attached to this message in MIME format is a copy of the traceback
buffer which contains the error message and other relevant details.

Have other Emacspeak users encountered this problem? Since Emacs 20.3 is
newer than Emacspeak 8.0, I realise that a change, or a bug, introduced in
version 20.3 could easily result in compatibility issues. For this reason,
I retained Emacs 20.2, which was not overwritten when 20.3 was installed.

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