HTML Viewer seems not running the website's Javascripts

I have an offline saved htm web page on sdcard to test Javascript. The default render on my phone seems to be HTML Viewer. But when I tried to open the page, the code didn't run. I know this because there's some html tag in the page I was added to detect this: /* my Javascripts */ The current browser can't run Javascript. which displays on the page: "The current browser can't run Javascript." So how can I enable Javascript in HTML Viewer? Both Opera and Browser are somehow can't found out the file when I typed in the address textbox: file://localhost/sdcard/page.htm The problem exist on almost any phone. But the later just works on some of my phone. Another not.