FULL PRODUCT VERSION :
java version "1.6.0_20"
Java(TM) SE Runtime Environment (build 1.6.0_20-b02)
Java HotSpot(TM) Client VM (build 16.3-b01, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7600]

A DESCRIPTION OF THE PROBLEM :
The compiler fails if a base interface includes a clone() method and an extended interface has multiple generic types. The error message is the same as Bug ID: 4185308 but the cause is different.
(Note that the sample code compiles correctly in the Eclipse Java compiler.)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Put the source code for an executable test case into two separate files in the same directory. Compile them. You should get a compiler error.


ERROR MESSAGES/STACK TRACES THAT OCCUR :
SubType.java:1: clone() in java.lang.Object cannot implement clone() in BaseType; attempting to assign weaker access privileges; was public
public interface SubType<T extends BaseType & java.io.Closeable> extends BaseType {
                         ^
1 error


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
public interface BaseType {
    BaseType clone() throws CloneNotSupportedException;
}

public interface SubType<T extends BaseType & java.io.Closeable> extends BaseType {
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Modify SubType so that the generic type parameter T extends only BaseType, not Closeable.