>>16
Dude, your link compares Classpath to JDK1.5. As in what Sun released with Java 5, you know the one with half-assed templates and everything.
GNU's java compiler GCJ doesn't support most of the Java 4 syntax extensions yet, let alone generics. It's a bit misplaced to complain about Classpath's java.lang.Boolean implementing java.lang.Comparable rather than the generic version (which is likely just a sub-interface of Comparable in the first place).