Multi JRE support fails in Netscape on Windows

Multi JRE support is failing in Netscape browser.When
Merlin is installed on a system which already has the
ladybird installed and running the applets using
specifically with the MIME type for ladybird
doesn't recognise the Plug-in .This breaks the Multi JRE support
of ladybird co-existing with Merlin.
This problem occurs only in Netscape browser when a Java Plug-in version
specific "CLSID" is used in IE loads the version of Plug-in correctly.

Also, Noticed that the NPJava131.dll in the Netscape/plugins directory
is removed when Merlin is installed on the System with ladybird
co-existing.

To reproduce the Problem:
_________________________

1. Install ladybird.
2. Run the following applet in Netscape4.x which uses
   "1.3.1" MIME type.

 http://sqesvr.eng/deployment2/sridhare/ws-07-2000/tests/multiversion/solaris/uniquefiles/version131.html

  This applet load fine using Java Plug-in 1.3.1

3. Install Java Plug-in Merlin build 59

4. Load the following applet .

http://sqesvr.eng/deployment2/sridhare/ws-07-2000/tests/multiversion/solaris/uniquefiles/version140.html

5. Applet is loaded fine using the Java Plug-in version 1.4.0

6. Load the Applet using MIME-type 1.3.1 again.

http://sqesvr.eng/deployment2/sridhare/ws-07-2000/tests/multiversion/solaris/uniquefiles/version131.html

The applet is not loaded and the Plug-in is not recognised.
This is not the behaviour in IE.Tested on NT/IE4/Netscape4.72
with ladybird-rc1 and Merlin build59.

NPJava131.dll from plug-in's directory should not be removed when Merlin is
installed.