signature exception on an app that isn't signed

[Doug Hoover]

A couple of people in my group have been getting a jarfile signature
exception (below), though

- they are running an application, not an applet
- they haven't messed with the java.security file
- this happens when a class in a jar file has already been loaded and
is trying to load another class in that jar file
- re-installing java (J2SDK1.4.0 in this case) does not help

They offending systems are running Windows XP sp1. The rest of the
people in the group, who have nominally the same configuration, don't
have this problem.

Any ideas?

Thanks

doug

java.lang.SecurityException: cannot verify signature block file
META-INF/ZIGBERT

at
sun.security.util.SignatureFileVerifier.process(SignatureFileVerifier
.java:148)
at java.util.jar.JarVerifier.processEntry(JarVerifier.java:281)
at java.util.jar.JarVerifier.update(JarVerifier.java:194)
at java.util.jar.JarFile.initializeVerifier(JarFile.java:250)
at java.util.jar.JarFile.getInputStream(JarFile.java:312)
etc.