It's probably related to your operating system or its previous java being Japanese or somehow related to Japanese fonts on your system. LW installers give you an option to choose which language to use for the installation on the 1st installer window.
For Java, I don't know but probably recognises something on your OS that is Japanese & the text used then defaults to Japanese. Can you see an option to change the language?
Instead of 'that' version of Java (1.4.2 by Blackwell), instead use the Sun Java version which is better:
Java 1.5 (take the JRE) 3rd on list!
I have my browser set to Japanese text at present, & the sun site gives me an option to switch over to a page in Japanese, but the page is in english.