validwhen + struts 1.1

[Vara Prasad Reddy]

I am currently using struts 1.1. Is there a way I can use the "validwhen" functionality of future coming struts 1.2.   Something like I can take only the class files of validwhen and use it along with struts 1.1   can someone detail me on this?   Thanks in advance Vara Prasad