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Right now, you don't want to know how it works, what your options are, about proxy tickets, or about why it is the way it is: you just want it to work.
Getting it
Download cas-security-provider 3.0.0x
Use a recent JRE 1.4. I don't think CAS Java Client 2.1.0 will run under JRE 1.3 or earlier, but I haven't tried.
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