unparsed-entity-uri ??

Hi!
I'm using:
Xerces Java Parser 1.2.1 Release
Xalan-Java version 1.2
i have a problem parsing url's (http://...) ,i want to use some kind of url
Encoding.
I have found this: 'unparsed-entity-uri' in the XSLT 1.0 spec. but it dont
seem to work.
I this a bug? Is there any other way to url Encode in XSLT ?
Using other functions in XSLT, or using other xsl: commands?
I only need to replace space with + and 'å','ä','ö' with
'&E4;','&E6;','&F4;'...
It dosent have to be perfect.. 
(this is the error message i get)
java.lang.NullPointerException
        at org/apache/xalan/xpath/dtm/DTMLiaison.getUnparsedEntityURI
(DTMLiaison.java:359)
        at org/apache/xalan/xpath/FuncUnparsedEntityURI.execute
(FuncUnparsedEntityURI.java:89)
        at org/apache/xalan/xpath/FuncLoader.execute (FuncLoader.java:108)
        at org/apache/xalan/xpath/Function.execute (Function.java:115)
        at org/apache/xalan/xpath/XPath.executeFunction (XPath.java:1271)
        at org/apache/xalan/xpath/XPath.execute (XPath.java:1380)
        at org/apache/xalan/xpath/XPath.execute (XPath.java:1354)
        at org/apache/xalan/xpath/XPath.execute (XPath.java:311)
        at org/apache/xalan/xslt/ElemValueOf.execute (ElemValueOf.java:186)
        at org/apache/xalan/xslt/ElemTemplateElement.executeChildren
(ElemTemplateElement.java:657)
        at org/apache/xalan/xslt/ElemTemplate.execute
(ElemTemplate.java:143)
        at org/apache/xalan/xslt/ElemCallTemplate.execute
(ElemCallTemplate.java:137)
        at org/apache/xalan/xslt/ElemTemplateElement.executeChildren
(ElemTemplateElement.java:657)
        at org/apache/xalan/xslt/ElemTemplateElement.childrenToString
(ElemTemplateElement.java:721).....

Thanks in advance.
/Anders
  Anders Carlberg <anders.carlberg@xxxxxxxxxxxx>
  Developer, isMobile, Aurorum 2, S-977 75 Luleå, Sweden
  Phone: +46(0)920-75561
  Mobile: +46(0)70-316 95 11 Fax: +46(0)70-383 38 17



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