Element name character range

Hello, I have been supporting LibreOffice, which uses Orcus v0.16. We have received the following bug report 141672 which states: "If there are some accented characters in a XML tag, the XML source import can't open this file."

For example, an element like: <Précision>

Will cause this error during parsing: Malformed XML error: malformed_xml_error: name must begin with an alphabet, but got this instead '�' (offset=612)

It writes that because the 'é' is not in the range [a-zA-Z_], but according to the XML specification, a much wider range of characters than that is valid in an element name.