We had a similar issue with the installation itself failing (on NT box). We had to remove the references to earlier (1.1, 1.2) versions of the JRE environments in the following hive (we had 1.3.0 JRE installed) :
HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment
You should export the full key in its original form before you make any changes to it in case you need to restore (as long as you have 1.3 installed, you’ll be okay). Then run the installer for the adapters, it will complete.
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