Preverifing a jar file in j2me

From: D123 (dac.tran_at_blisterent.com)
Date: 02/29/04 

Date: 28 Feb 2004 15:09:00 -0800

I'm currently tring to preverify a jar file in j2me. (I already know
how to preverify classes, but not preverifying a jar file). Does
anyone have any idea? I need to preverify a jar file because I want
to use ProGuard obfuscator for j2me, but it requires me to preverify
the compiled project jar file before I can run the Proguard obfuscator
on it. I don't want to use the built in Wireless ToolKit feature
because I need the obfuscator to ignore my Native methods.
I've tried:
preverify file.jar

But I get the following errors:
Error preverifying class ...
   java/lang/NoClassDefFoundError: ...

Thanks for your help.