Incorrect UTF8 conversion for sequence fc 80 80 8f bf bf

SYNOPSIS
--------
Incorrect UTF8 conversion for sequence fc 80 80 8f bf bf

OPERATING SYSTEM
----------------
All

FULL JDK VERSION
----------------
Java 6 (tested with 1.6.0_26)
Java 7 (tested with GA / b147)

PROBLEM DESCRIPTION from LICENSEE
---------------------------------
The UTF8 specification states that the maximal valid subpart should be replaced by a single fffd before moving to process the next one. In this case FC is invalid, therefore each subsequent byte should be treated as single byte.

TESTCASE
--------
public class RegTest {
    public static void main (String args[]) throws Exception {
            byte[] test1 = new byte[] {(byte)0xfc, (byte)0x80, (byte)0x80, (byte)0x8f, (byte)0xbf, (byte)0xbf};
            String s1 = stringToHex(new String(test1, "UTF8"));
            System.out.println(s1);
    }

    public static String stringToHex( String base ) {
        StringBuffer buffer = new StringBuffer();
        int intValue;
        for (int x = 0; x < base.length(); x ++) {
            intValue = base.charAt(x);
            String hex = Integer.toHexString(intValue);
            if (hex.length() == 1) {
                buffer.append("0" + hex + " ");
            } else {
                buffer.append(hex + " ");
            }
        }
        return buffer.toString();
    }
}

REPRODUCTION INSTRUCTIONS
-------------------------
1. javac RegTest.java
2. java RegTest

Actual Output:
fffd

Expected Output:
fffd fffd fffd fffd fffd fffd