Run RichFace 4.0 on GlassFish 3.1 get warning This page calls for XML namespace http://richfaces.org/a4j declared with prefix a4j but no taglibrary exists for that namespace

If you get "This page calls for XML namespace http://richfaces.org/a4j declared with prefix a4j but no taglibrary exists for that namespace" error when running RichFace 4.0 on GlassFish 3.1 with Eclipse, it is always because you didn't deploy the RichFace jar lib to GlassFish path. Try to export below jar files with deploy package

cssparser-0.9.5.jar,
guava-r08.jar,
richfaces-components-api-4.0.0.Final.jar,
richfaces-components-api-4.0.0.Final.jar,
richfaces-components-ui-4.0.0.Final.jar,
richfaces-core-api-4.0.0.Final.jar,
richfaces-core-impl-4.0.0.Final.jar,
sac-1.3.jar

1. Goto project properties
2. Click Deployment Assembly
3. Add above jar files

Done.