FULL PRODUCT VERSION :
java version "1.6.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.6.0-beta-b59g)
Java HotSpot(TM) Client VM (build 1.6.0-beta-b59g, mixed mode, sharing)


ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
I'm using a signed jar file named xxx.zip
When calling

  javap -classpath xxx.zip MyClass

I get a message

ERROR: could not find MyClass

However after renaming the file to xxx.jar and calling

  javap -classpath xxx.jar MyClass

It works fine.
It is reproducible with large signed jar files (>2MB) but seems to work fine with small, unsigned files

REGRESSION. Last worked in version mustang


REPRODUCIBILITY :
This bug can be reproduced always.