This is what I did in Dreamweaver:
(The name of the buttons...etc may not be accurate as I'm using a Chinese one)
There is a screenshot attached, please click
here.
1. Open a new html file.
2. Change the meta charset to iso-8859-1 first.
3. Click "split" button (between "source" and "design", on the left of the title of the html page). You'll see your working area split to: Upper the source code, down the actual visual stuff.
4. Type your Japanese characters in the visual stuff area.
5. You will see the converted corresponding &#xxxxx; codes in the source code area