[ BUILD # : 200509261930 ]
[ JDK VERSION : 1.5.0_04 ]

When I want to create a DTD constrained document, all is fine, except of DTD url which is included in XMLs <!DOCTYPE>
Example:
<!DOCTYPE taglib PUBLIC '-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN' 'null'>

Why null???

I created an OASIS resolver xml:
<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
         "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">

<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">                
 <public publicId="-//SPRING//DTD BEAN//EN"
uri="http://www.springframework.org/dtd/spring-beans.dtd"/>
 <uri name="http://www.springframework.org/dtd/spring-beans.dtd" 
uri="file:/D|/Soft/Development/Libraries/Java/DTDs/spring-beans.dtd"/>
</catalog>
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In which I used global uri for resolution (<public>) and local one as an alias (<uri>).
Why not to use <public> one in <!DOCTYPE>.