Hi
I am trying to use datatypes defined in xml file to check correctness
of input parameter values
To define needed datatypes following schema.xml file was created:

<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xmlns:pd="uri:myUri.com">
    <xsd:simpleType name="pd:width">
        <xsd:restriction base="xsd:positiveInteger">
            <xsd:maxLength value="4"/>
            <xsd:minInclusive value="20"/>
            <xsd:maxInclusive value="2000"/>
        </xsd:restriction>
    </xsd:simpleType>
    <xsd:simpleType name="pd:height">
        <xsd:restriction base="xsd:positiveInteger">
            <xsd:maxLength value="4"/>
            <xsd:minInclusive value="20"/>
            <xsd:maxInclusive value="2000"/>
        </xsd:restriction>
    </xsd:simpleType>
</xsd:schema>

When I'm trying to run program with types of parameters set to
pd:height and pd:width I get following exception:

org.apache.xpath.domapi.XPathStylesheetDOM3Exception: Prefix must
resolve to a namespace: xsd

When I'm defining parameter types to be xsd:PositiveInteger, everything
works fine
But if I only try to use prefix pd: I get that exception.

I went through stack trace but that led me nowhere...
I've used google, read quite a bit, but got to no satisfying
conclusions...
I'm new to xml, and got quite confused
Please help ^^