The main reason is, compilation problem due to missing jars/classes for jws file provided "${WSDL_FILENAME}Service_${WSDL_FILENAME}PortImpl.java". So, make sure that all jars/classes are set to its classpath as mentioned below.
1:
<target name="build"
depends="gen-serv,gen-client">
2:
<delete
dir="build"/>
3:
<jwsc
srcdir="${SERVER_SRC_DIR}" destdir="build/${WSDL_FILENAME}"
>
4:
<jws
file="${WSDL_FILENAME}Service_${WSDL_FILENAME}PortImpl.java"
compiledWsdl="lib/${WSDL_FILENAME}_wsdl.jar"
type="JAXWS">
5:
<WLHttpTransport
contextPath="${WSDL_FILENAME}Service"
serviceUri="${WSDL_FILENAME}Port"
portName="${WSDL_FILENAME}Port"/>
6:
<zipfileset dir="."
prefix="WEB-INF">
7:
<include
name="lib/${WSDL_FILENAME}_Client.jar" />
8:
</zipfileset>
9:
</jws>
10:
<classpath>
11:
<pathelement
path="${classpath}"/>
12:
<fileset
dir="${weblogic.jar.classpath}" >
13:
<include
name="**/*.jar"/>
14:
</fileset>
15:
</classpath>
16:
</jwsc>
17: </target>