I have learned from some web references that I can use image in place of default
browse button in file uploading, something that look like the following:
<input type="file" name="filename" style="display: none;" onchange="fullfilepath.innerHTML
= this.value;"/>

<span id="fullfilepath">&nbsp;</span>
<img src="someimage.gif" onclick="filename.click();" />
<input type="submit" value="submit" />

When I hit the submit button (type submit), it didn't get submitted the first
time, so I had to click it again and it go through, but the attachment was
somehow not included.

I tried to replace the submit button with a type="button" and use some javascript
to do the .submit(). Then I got access denied error.

Does anyone knows the workaround of this? Thanks!