Jsp and image cache problem

Hello,
In a jsp(running on tomcat) I switch two jpg files(1.jpg and 2.jpg) and redirect to the page that displays them.
The problem is that the files are really changed, but the page which displayed them needs manual refresh to "know" they are inter-changed.
What I have tried, but no success:
1) In the page which displayed them, I have tried to setup header:
response.setHeader("cache-control","no-cache, no-store,must-revalidate, max-age=-1");
response.setHeader("pragma","no-cache, no-store");
response.setDateHeader ("expires", -1);no difference, in both IE(6 and 7) and Firefox 2.
Also no result with html:
<meta http-equiv="Pragma" content="no-cache">
<meta http-equiv="Expires" content="-1">2) I have tried to a add a fake param on the images, like
<a href="1.jpg?<%=(new java.util.Date()).getTime() %">3) I have tried to add also a fake(time) parameter on the jsp which displayes the images, no result
How can I force the browser to know that I have inter-changed the images?
Any idea?
Thank you.</a>

to traja47 : could you be more specific about that post? Since there are 30,000 plus post about jsp and my sql, thank you very much.
to jSweep :
No exceptions.
just when i ran it, the page is all empty, then I used the VIEW-SOURCE of IE to see the source of the result page, it showed:
<html>
<head>
<title>Accessing data in a database</title>
</head>
<body>
</body>
</html>
all the parts related to java are gone. don't know why.

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