Impossible to read rt.jar classes??

Hi,
I noticed that recent versions of the rt.jar from Sun are compressed in a way making it impossible to extract files from it?
I need to do this from a Java tool I am creating, but I end ut with a:
java.util.zip.ZipException: invalid CEN header format
And when trying to extract files using winzip I get a CRC error...
I suppose this is a way of protecting the holy rt.jar file from evil hackers or virus programs or something, but for me it is quite frustrating!
I really need to extract these files programatically, are there any workarounds? And, how was this extraction protection added in the first place?

Have you tried:
jar -xvf rt.jar
V.V.
Yes, that will extract the files even from those CRC-error rt.jar files, however I really need to do this in my own program directly on the rt.jar file, this is an important feature of the tool I am making, unfortunately.
It works on almost every JAR file, except the ones coming with the JRE, which are the most important ones. Even the JDK rt.jar seems fine, but that still does not help me as I cannot rely on any particular version of the rt.jar to be available on my users computer...

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When the collection classes first came out, I think they were available in a separate jar (although the package name may be slightly different). If it's just collection classes, that might be worthwhile looking at.
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user10196088 wrote:
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Impossible to read rt.jar classes??

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