Abnormal behavior for java plugin 1.3.0 and 1.3.1

Question

Hi,
I've developed a java applet which renders svg images. I am working in a constrained environment where both java plugin 1.3.0_02 and java plugin 1.3.1_02 are installed.
the code for the embedded applet in html,
<object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"
WIDTH =" 600" HEIGHT =" 700">
<param NAME = CODE VALUE ="MyViewerApplet.class" >
<param NAME = ARCHIVE VALUE ="required.jar" >
<param NAME="type" VALUE="application/x-java-applet;version=1.3">
<param NAME="IMAGES" VALUE="http://localhost:8889/images/">
<param NAME="HOMESVG" VALUE="http://localhost:8889/mysvg.svg">
<COMMENT>
<embed type="application/x-java-applet;version=1.3"
java_CODE ="MyViewerApplet.class"
java_ARCHIVE ="required.jar"
WIDTH =" 600"
HEIGHT =" 700"
pluginspage="http://java.sun.com/products/plugin/1.3/plugin-install.html"
IMAGES="http://localhost:8889/images/">
HOMESVG="http://localhost:8889/mysvg.svg">
<noembed></noembed></embed>
</COMMENT>
</object>
One note about the applet, the applet's loads RenderingCanvas.class from required.jar.
Now when i open Internet Explorer , it loads the 1.3.0 plugin and when i open Netscape Navigator it loads the 1.3.1 plugin !!!.
Well thats not the biggest problem. The applet works correctly in Netscape Navigator. However, the java plugin 1.3.0 in internet explorer complains -> NoClassDefFoundError org.xxx.yyy.RenderingCanvas (Note: it doesn't say ClassNotFoundException).
Another thing, why does the plugin call the applet's INIT and START methods before the jar archive has even been loaded(thats what the output shows). Wouldnt the plugin always complain that the file was not found since the jar archive has not been loaded.
Although my description does seem a bit vague, does anyone have an idea why this could be ?
Thanks in advance.
A.

Answer 1

One note about the applet, the applet's loads
RenderingCanvas.class from required.jar.
Now when i open Internet Explorer , it loads the 1.3.0
plugin and when i open Netscape Navigator it loads the
1.3.1 plugin !!!.What Sun calls "dynamic versioning" allows you to specify a major version number as required -- any minor version will match. For example, "any 1.3 or higher", "any 1.4 or higher". This is described in Sun's plugin developer's guide.
Well thats not the biggest problem. The applet works
correctly in Netscape Navigator. However, the java
plugin 1.3.0 in internet explorer complains ->
NoClassDefFoundError org.xxx.yyy.RenderingCanvas
(Note: it doesn't say ClassNotFoundException).I don't know.
Another thing, why does the plugin call the applet's
INIT and START methods before the jar archive has even
been loaded(thats what the output shows). Wouldnt the
plugin always complain that the file was not found
since the jar archive has not been loaded.Are you saying that MyViewerApplet.class is available directly from the server, and the remaining classes that it depends on are in required.jar? If so, this is normal. Java (or at least common Java implementations) load classes as needed. This means that MyViewerApplet should run fine until it encounters a class which is in required.jar, at which time it will have to wait for the loading to complete. If you want it all to load before anything starts, put MyViewerApplet.class in the jar as well.