According to the Appendix section in JAXRPC specification TABLE 18-1 XML Schema support in JAX-RPC specification:

XML Schema: Derivation of a complex type from a simple Type

Example of XML Schema fragment and/or XML Schema instance:
----------------------------------------------------------------------------------------
<xsd:element name="internationalPrice">
<xsd:complexType>
<xsd:simpleContent>
<xsd:extension base="xsd:decimal">
<xsd:attribute name="currency" type="xsd:string"/>
</xsd:extension>
</xsd:simpleContent>
</xsd:complexType>
</xsd:element>

Support in JAX-RPC 1.1: Required

When it is extension from simpleTypes like xsd:string, xsd:integer etc from the JAXRPC Spec TABLE 4-1 Java mapping for the built-in simple XML data types, that are mapped to a Java Type which are Wrappers, wstools works properly with the mapping, but when the types are mapped to simpleTypes like xsd:int, xsd:boolean they are mapped to their wrappers which is wrong according to the Table 4-1 in the spec and when the simple type is xsd:base64Binary or xsd:hexBinary instead it fails to map properly to its Java Type byte[]. Instead it maps the type as [B and the source becomes uncompilable.