Have you guys ever concluded about this?
Now I've met one,very strange,don't know why.
My code:
<td valign="top">
<input type="text" />
<iframe scrolling="no" height="21px" frameborder="0" width="62px" marginheight="0" marginwidth="0" src="Server/SecCode.php">
</iframe>
</td>
But it turns out to be that the "input" is valigned to the bottom,while "iframe" to the top.
I agree, a little more information will be helpful track down this problem. If only for debugging purposes, you may want to try:
<td valign="top">
<input type="text" /><Br/>
<iframe scrolling="no" height="21px" frameborder="0" width="62px" marginheight="0" marginwidth="0" src="Server/SecCode.php">
</iframe>
valign would only work if you used other kinds doctypes on your page, probably you have something like:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
Try to remove the doctype, what isn't a good practice, and see if it's works..
So put only the html tag..