1. Minimal Weblogic version number should be 10.3.6. This release contains jsf 2.0 implementation as a jar file that should be installed separately.
We deploy $WEBLOGIC_HOME/modules/javax.jsf_1.1.0.0_1-2.jar as a library onto Weblogic server.

2. Our application should contain:
in web.xml:

    <context-param>
        <param-name>com.sun.faces.expressionFactory</param-name>
        <param-value>com.sun.el.ExpressionFactoryImpl</param-value>
    </context-param>

in weblogic.xml:

 <library-ref>
  <library-name>jsf</library-name>
  <specification-version>2.0</specification-version>
  <implementation-version>1.0.0.0_2-0-2</implementation-version>
  <exact-match>true</exact-match>
 </library-ref>

 <container-descriptor>
    <prefer-application-packages>
       <package-name>com.sun.el.*</package-name>
       <package-name>javax.el.*</package-name>
    </prefer-application-packages>
 </container-descriptor>

3. The following jars should be included as dependencies into pom.xml:

        <dependency>
            <groupId>org.glassfish.web</groupId>
            <artifactId>el-impl</artifactId>
            <version>2.2</version>
        </dependency>

        <dependency>
            <groupId>javax.faces</groupId>
            <artifactId>jsf-api</artifactId>
            <version>2.0</version>
        </dependency>