I am seeing a strange error in both 4.5 and also in 4.5.1.

The following code caused the XSLT to not save, and the whole site (including published pages) to stop working for about 2 minutes (or what seems like hours).

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp "&#x00A0;">
                            <!ENTITY hidden "umbracoNaviHide = 1">
                            <!ENTITY node "*[@isDoc]">
]>
<xsl:stylesheet 
  version="1.0" 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
  xmlns:msxml="urn:schemas-microsoft-com:xslt"
  xmlns:umbraco.library="urn:umbraco.library" xmlns:Exslt.ExsltCommon="urn:Exslt.ExsltCommon" xmlns:Exslt.ExsltDatesAndTimes="urn:Exslt.ExsltDatesAndTimes" xmlns:Exslt.ExsltMath="urn:Exslt.ExsltMath" xmlns:Exslt.ExsltRegularExpressions="urn:Exslt.ExsltRegularExpressions" xmlns:Exslt.ExsltStrings="urn:Exslt.ExsltStrings" xmlns:Exslt.ExsltSets="urn:Exslt.ExsltSets" 
  exclude-result-prefixes="msxml
 umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes 
Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings 
Exslt.ExsltSets ">


<xsl:output method="xml" omit-xml-declaration="yes"/>

<xsl:param name="currentPage"/>

<xsl:template match="/">

  <xsl:variable name="homeMenu" select="/macro/homeItem"/>
  <xsl:variable name="homePage" select="umbraco.library:GetXmlNodeById($homeMenu)"/>
  <ul>
    <xsl:apply-templates select="$homePage | $homePage/&node;"/>
  </ul>

</xsl:template>
<xsl:template match="&node;">
  <li>
    <a href="{umbraco.library:NiceUrl(@id)}">
      <xsl:if test="@id = $currentPage/@id">
        <xsl:attribute name="class">
          selected
        </xsl:attribute>
      </xsl:if>
      <xsl:value-of select="@nodeName"/>
    </a>
  </li>
</xsl:template>
    <xsl:template match="&node;[&hidden;]"/>    
</xsl:stylesheet>

If I change the line:

<xsl:variable name="homeMenu" select="/macro/homeItem"/>

To read

<xsl:variable name="homeMenu" select="1234"/>

Then the XSLT saves and everything is fine.

It does not seem to matter if the item has been created in the macro or not.

What am I missing/doing wrong?

Thanks

TT