I fixed it with a simple xslt
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:msxsl="urn:schemas-microsoft-com:xslt" xmlns:var="http://schemas.microsoft.com/BizTalk/2003/var" exclude-result-prefixes="msxsl var s0" version="1.0" xmlns:s0="http://tempuri.org/">
<xsl:output omit-xml-declaration="yes" method="xml" version="1.0" />
<xsl:template match="/">
<xsl:apply-templates select="/s0:getDocumentsReqResponse" />
</xsl:template>
<xsl:template match="/s0:getDocumentsReqResponse">
<xsl:value-of select="normalize-space(s0:getDocumentsReqResult)" disable-output-escaping="yes" />
</xsl:template>
</xsl:stylesheet>
That also does the trick. :-)