URGENT: New JAR file NOT being pushed to web clients.

Question

Greetings...
When our web app first came to market, some of our customers were still using a dial-up connection. Therefore, since one of our web pages uses an applet, it was decided to ship the necessary JAR files to clients on an installation CD, rather than burden our dialup customer with having the JAR files pushed out to them over the line. The jar files are installed in the C:\Program Files\JavaSoft\JRE\1.3\lib\ext directory on the client computers.
Don't ask why, but we are now attempting to have our web site push out a new JAR file to just one of our clients, but the problem I'm running into is that if the OLD jar file already exists in the C:\Program Files\JavaSoft\JRE\1.3\lib\ext directory, the NEW jar file isn't pushed out by the website. My understanding was that the system would automatically detect if the JAR file on the client was older than the JAR file on the server and would then push the newer JAR file out to the client, but obviously, I'm missing something.
Any help/suggestions you can provide would be greatly appreciated. Following is the kludgy ASP code for this...
<%szCustomer = getCustomer();%>
<%if (szCustomer="SccTest") {%>
<!-- NEW CODE: Push out the NEW JAR file with the meters to feet change. -->
<OBJECT classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93" width="600" height="400" name="SccMapplet"
codebase="http://java.sun.com/products/plugin/1.3/jinstall-13-win32.cab#Version=1,3,0,0" ID="IMSMap" VIEWASTEXT>
<PARAM NAME="code" VALUE="com.scc.mapplet.SccMapplet">
<param name="archive" value="SccMapplet.jar,xml.jar,iiimp.jar,jai_codec.jar,jai_core.jar,mlibwrapper_jai.jar">
<PARAM NAME="scriptable" VALUE="true">
<PARAM NAME="type" VALUE="application/x-java-applet;version=1.3">
<PARAM NAME="WebAXL" VALUE="/EweData/<%=getCustomer()%>.axl">
<PARAM NAME="Session" VALUE="<%=SCCSession.SessionID%>">
<COMMENT>
<EMBED type="application/x-java-applet;version=1.3" width="600" height="400"
code="com.scc.mapplet.SccMapplet" archive="SccMapplet.jar,xml.jar,iiimp.jar,jai_codec.jar,jai_core.jar,mlibwrapper_jai.jar"
pluginspage="http://java.sun.com/products/plugin/1.3/plugin-install.html">
<NOEMBED>
</COMMENT>
No Java 2 SDK, Standard Edition v 1.3 support for APPLET!!
</NOEMBED></EMBED>
</OBJECT>
<%} else {%>
<!-- OLD CODE: Use the JAR file already installed on C:\Program Files\JavaSoft\JRE\1.3\lib\ext -->
<object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"
width=600 height=400 ID="IMSMap" name="SccMapplet" VIEWASTEXT>
<param NAME="code" VALUE="com/scc/mapplet/SccMapplet">
<param NAME="name" VALUE="IMSMap">
<param NAME="SCRIPTABLE" VALUE="TRUE">
<param NAME="type" VALUE="application/x-java-applet;version=1.2">
<PARAM NAME="WebAXL" VALUE="/EweData/<%=getCustomer()%>.axl">
<PARAM NAME="Session" VALUE="<%=SCCSession.SessionID%>">
<comment>
<embed type="application/x-java-applet;version=1.2" width="600" height="480" code="com/esri/ae/applet/IMSMap" name="IMSMap">
<noembed>
</COMMENT>
No JDK 1.2 support for APPLET!!
</noembed></embed>
</object>
<%}%>

Answer 1

I guess the problem is, that your local jar file's classes copied to the JRE's ext directory have higher priority. The JRE does not store your applet jar locally and so does not overwrite anything you may have installed, it only executes the jar file given by the browser which may cache it or not.
Why don't you use the Java Webstart technolgy? It's pretty simple to use it. Customers would have to download every new jar version only once and Webstart will take care that the local version is up-to-date every time your app is started.