javac reports deprecation warnings for deprecated types used in deprecated metho

FULL PRODUCT VERSION :
java version "1.6.0_21"
Java(TM) SE Runtime Environment (build 1.6.0_21-b07)
Java HotSpot(TM) Client VM (build 17.0-b17, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
I have a java library whose classes/methods I'm deprecating because I've come up with a new mechanism for achieving the same functionality. The deprecated classes/methods refer to one another, and for the most part I don't get deprecated warnings for these (and this is good). But for the case where a method in one deprecated class takes an argument of a different deprecated class, I get a warning (which I think is a javac bug) stating that the argument class is deprecated. Furthermore, @SuppressWarnings("deprecation") doesn't help (which I'm almost certain is a bug).


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
X.java:
@Deprecated public class X
{
    void add(Y y)
    {
    }
}

Y.java:
@Deprecated public class Y
{
}

Compile them:
javac -deprecation *.java


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
No warnings because X is deprecated, so methods in it that take arguments of deprecated type Y shouldn't be a problem.
ACTUAL -
X.java:15: warning: [deprecation] Y in unnamed package has been deprecated
    void add(Y y)

The line number would be different for you; I removed some comments generated by my code formatter.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
See Steps to Reproduce for the example.
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Don't deprecate class Y, but rather deprecate all of the methods in it. Very annoying for large classes Y.