anyURI mystery help

I did spend some 2 hours trying to solve this problem with google, without any result.

 I have the following simple xml file
<?xml version="1.0" encoding="UTF-8"?>
<message xmlns:idm="http://www.bellsouth.com/idm"  
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.bellsouth.com/idm"
xsi:schemaLocation="http://www.bellsouth.com/idm file://wherever_schema_is_stored/NMS-LESYG-IF_WFAC_ALL.xsd"
system="DSLNMS" systemInstance="WFAC" cuid="WfacIDM"
messageID="CYJEFF69-1115748309103000" clientID="jbbos" priority="1" timeToLive="0">
<responsePayload>
<returnStatus>Success</returnStatus>
</responsePayload>
</message>

But when I try to validate this file against a schema, I get the error that  "file://wherever_schema_is_stored/NMS-LESYG-IF_WFAC_ALL.xsd  is not valid anyURI".
( Im using xerces by the way. with JDK 1.4 )

1.     at com.bellsouth.snt.util.xml.FastDomParser.validate(FastDomParser.java:146)
        at com.bellsouth.snt.util.xml.XSLTTransformer.transform1To1(XSLTTransformer.java:91)
        ... 10 more
Caused by: :::::2:387:cvc-datatype-valid.1.2.1: 'file://wherever_schema_is_stored/NMS-LESYG-IF_WFA
C_ALL.xsd' is not a valid value for 'anyURI'.
        at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
        at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator$XSIErrorReporter.reportError(Unknown Sourc
e)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.reportSchemaError(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.processOneAttribute(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.processAttributes(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.handleStartElement(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.startElement(Unknown Source)
        at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source)
        at org.apache.xerces.impl.XMLNSDocumentScannerImpl$NSContentDispatcher.scanRootElementHook
(Unknown Source)
        at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatc
h(Unknown Source)
        at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
        at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown Source)
        at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown Source)
        at com.bellsouth.snt.util.xml.FastDomParser.validate(FastDomParser.java:139)


2. Which is the RFC that defines the file:// type URI syntax


Thanks for reading
--sony