Disk Space "leaking" in Java Application Using java.io.RandomAccessFile

I have noted this behaviour in both java version 1.2.1 and 1.3.1 on Solaris 5.8.
I have a java application that is essentially "tailing" a very large log file.
The program opens a RandomAccessFile in read-only mode and calls readLine on the file as long as the file is getting written to.
If the file stops getting updated the program assumes the logfile has been moved/rotated/wrapped (by an external process) and the program the calls close and then reopens the file to allow the program to start reading from the new file and to allow the O/S to free up the system resources.
It appears that the program is not actually closing the filehandle or releasing the disk space and eventually the disk fills up.
When this happens the program is stopped and restarted and the disk space is freed up.
We have run the pfiles command against the running process and have confirmed that the old filehandles are still open.
I have attached what I think to be the relevant code lines below:
RandomAccessFile filehandle = null;
boolean reopen = true;
boolean connected = true;
while(connected)
if (reopen)
while(! new File(filename).exists())
doSleep (filewaittime);
filehandle = new RandomAccessFile(filename, "r");
while (file_being_updated)
// read from the file etc.
filehandle.close();
filehandle = null;
reopen = true;
The reopen flag is set to false in code not shown here.
I have verified that the block of code that calls close() on the filehandle and sets it to null is being executed when the logfile is moved externally.

Hmmmm. Sounds like a hint to me :)
I am still experimenting but I will certainly try moving to the latest JDK and report a bug if I don't figure this out on my own.
Thanks.

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