An attempt to compile the following code (to be placed in Main.java):
-----------------------------------------------
public class Main {

    public static void main(String[] args) {
        E.A.test();
    }

}

enum E implements X{

    A {
        public void test() {}
    }
    
}

interface X {
    public void test();
}
-----------------------------------------------

Fails with this error:

Main.java:4: cannot find symbol
symbol : method test()
location: class E
        E.A.test();
           ^
1 error

If the Main class is moved at the end of the file, it can be compiled fine.

The same problem can be reproduced when Main, E and X are in individual files. The problem occurs when the compiler is invoked as:
javac Main.java E.java X.java
but does not appear when the compiler is invoked as:
javac E.java X.java Main.java

Tested on:
>java -version
java version "1.5.0_12"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_12-b04)
Java HotSpot(TM) Server VM (build 1.5.0_12-b04, mixed mode)

>java -version
java version "1.6.0_05-ea"
Java(TM) SE Runtime Environment (build 1.6.0_05-ea-b04)
Java HotSpot(TM) Tiered VM (build 1.6.0_05-ea-b04, mixed mode)

See also the original NetBeans issue:
http://www.netbeans.org/issues/show_bug.cgi?id=121458