Adding newline changes output formatting

I have XML input:
  <?xml version="1.0"?>
  <packages>
    <package>
      <category>Applications/Internet</category>

      <install-name>test</install-name>
and want to duplicate this as output using the XSLT input:
  <xsl:template match="/">
    <xsl:element name="packages">
      <xsl:for-each select="packages/package">
        <xsl:element name="package">
          <xsl:copy-of select="category"/>

          <xsl:if test="string(category)">
            <xsl:text>&#10;</xsl:text>
          </xsl:if>

        ...
        </xsl:element>
      </xsl:for-each>
    </xsl:element>
  </xsl:template>

Using xsltproc 1.0.23 I get:
  <?xml version="1.0"?>
  <packages>
    <package><category>Applications/Internet</category>
  </package>
  </packages>

If I remove:
          <xsl:if test="string(category)">
            <xsl:text>&#10;</xsl:text>
          </xsl:if>
I get:
  <?xml version="1.0"?>
  <packages>
    <package>
      <category>Applications/Internet</category>
    </package>
  </packages>

So why does inserting a newline mess up the output?

-- 
albert chin (china@xxxxxxxxxxxxxxxxxx)

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