I have a little macro that I am reading RSS feeds with using

umbraco.library:GetXmlDocumentByUrl()

I have it working using a BBC news RSS feed, but as soon as I change the URL to an eBay RSS feed URL like below

http://rss.api.ebay.com/ws/rssapi?FeedName=SearchResults&dfsp=32&from=R6&nojspr=y&output=RSS20&saaff=afepn&siteId=3&afepn=5336246701&customid=&satitle=vht&fbfmt=1&sabfmts=0&sascs=0&fss=1&saslop=1&sasl=usauto1997&fsop=2&fsoo=2

The XSLT won't save and the error I get is this???

System.Xml.XmlException: '=' is an unexpected token. The expected token is ';'. Line 24, position 137. 
at System.Xml.XmlTextReaderImpl.Throw(Exception e) 
at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args) 
at System.Xml.XmlTextReaderImpl.ThrowUnexpectedToken(String expectedToken1, String expectedToken2) 
at System.Xml.XmlTextReaderImpl.ThrowUnexpectedToken(Int32 pos, String expectedToken1, String expectedToken2) 
at System.Xml.XmlTextReaderImpl.HandleEntityReference(Boolean isInAttributeValue, EntityExpandType expandType, Int32& charRefEndPos) 
at System.Xml.XmlTextReaderImpl.ParseAttributeValueSlow(Int32 curPos, Char quoteChar, NodeData attr) 
at System.Xml.XmlTextReaderImpl.ParseAttributes() 
at System.Xml.XmlTextReaderImpl.ParseElement() 
at System.Xml.XmlTextReaderImpl.ParseElementContent() 
at System.Xml.XmlTextReaderImpl.Read() 
at System.Xml.Xsl.Xslt.XsltInput.ReadNextSiblingHelper() 
at System.Xml.Xsl.Xslt.XsltInput.ReadNextSibling() 
at System.Xml.Xsl.Xslt.XsltInput.MoveToNextSibling() 
at System.Xml.Xsl.Xslt.XsltLoader.LoadInstructions(List`1 content, InstructionFlags flags) 
at System.Xml.Xsl.Xslt.XsltLoader.LoadTemplate(NsDecl stylesheetNsList) 
at System.Xml.Xsl.Xslt.XsltLoader.LoadRealStylesheet() 
at System.Xml.Xsl.Xslt.XsltLoader.LoadDocument() 
at System.Xml.Xsl.Xslt.XsltLoader.LoadStylesheet(XmlReader reader, Boolean include)

Any ideas why its doing this?  As I say it saves and works a treat with the BBC URL's??