Width Of Text Input Box Vs. Password Input Box

I have the following HTML/CSS:

HTML:

<div id="stealth_form">
<form name="stealthme" action="" onSubmit="return
initializeSearch(this);">
<input type='password' name='query' size=16>
</form>
</div>

<div id="search_form">
<form name="searchme" action="" onSubmit="return
initializeSearch(this);">
<input type='text' name='query' size=16>
</form>
</div>

CSS:

#search_form
{
position: absolute;
top: 600px;
left: 210px;
height: 50px;
width: 300px;
background-color: rgb(70,70,70);
visibility: visible;
}

#stealth_form
{
position: absolute;
top: 600px;
left: 210px;
height: 50px;
width: 300px;
background-color: rgb(70,70,70);
visibility: hidden;
}

OK. I use javascript to dynamically set the visibility of #search_form
to 'hidden' and the visibility of #stealth_form to 'visible'. In
mozilla/firefox there is no visual difference. In IE the #stealth_form
input box is 1 pixel wider, and when the change occurs it catches the
users eye and looks strange.

Any ideas / workarounds? I know this is off topic for this group, but
most on this group know an awful lot about HTML / CSS, and I thought it
was worth a shot.