[Default Bundle] Missing Field

[red phoenix]

I use JDK1.6,tomcat5.0.28,Struts1.2.9,I run Bundles Example
Form<http://localhost:8080/struts-examples/validator/viewBundleExamples.do>
of
struts-examples.war,when I click Save button,I find the Field Address
say "[Other
Bundle]Missing Field: Address(Other Bundle) "
Why raise above error?  How to correct it?