------------- test code ---------------
    public boolean xferTest02() {
String testName = "xferTest02" ;
byte[] dstData ;
long fileLength ;
FileChannel fc1, fc2 ;
MappedByteBuffer b ;

String srcFileName = "src." + testName ;
String dstFileName = "dst." + testName ;

byte[] srcData = Helper.getRandomByteArray(MIN_DATA_SIZE, MAX_DATA_SIZE);
try {
int bytesWritten ;
int bytesToWrite ;
int startPosition ;

// get filechannel for the source file.
fc1 = Helper.openRWFileChannel(srcFileName) ;
// write out data to the file channel
bytesWritten = fc1.write(ByteBuffer.wrap(srcData)) ;

// get filechannel for the dst file.
fc2 = Helper.openRWFileChannel(dstFileName) ;
bytesToWrite = srcData.length/2 ;
startPosition = srcData.length/4 ;
System.out.println("srcData.length=" + srcData.length
                      + ", bytesToWrite=" + bytesToWrite
                      + ", startPosition=" + startPosition);

bytesWritten = fc1.transferTo(startPosition, bytesToWrite, fc2); // <<< fails here


} catch (Exception e) {
return TestHelper.testFail(testName + " FAIL: Unexpected Exception", e);

}
    }

---------- result on windows 98 -------------

H:> java FCtransferTo

srcData.length=4984, bytesToWrite=2492, startPosition=1246

xferTest02 FAIL: Unexpected Exception
java.io.IOException
at sun.nio.ch.FileChannelImpl.unmap0(Native Method)
at sun.nio.ch.FileChannelImpl.unmap(FileChannelImpl.java:414)
at sun.nio.ch.FileChannelImpl.transferTo(FileChannelImpl.java:272)
at FCtransferTo.xferTest02(FCtransferTo.java:216)
-------------------

Works OK on Solaris.

build 1.4.0-beta_refresh-b72