Due to the issue of ANTLR that weblogic 10 uses internally, we need to add a file WEB-INF/weblogic.xml with the following contents to solve the conflict:
<?xml version="1.0" encoding="UTF-8"?>
<weblogic-web-app
xmlns="http://www.bea.com/ns/weblogic/90"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.bea.com/ns/weblogic/90
http://www.bea.com/ns/weblogic/90/weblogic-web-app.xsd">
<container-descriptor>
<prefer-web-inf-classes>true</prefer-web-inf-classes>
</container-descriptor>
</weblogic-web-app>
This file make Weblogic use classes and libraries in the web application before other libraries in the classpath.