Transparent style is not supported in IE

I believe that you are looking for this setting (for IE8 and below):
 

filter:alpha(opacity=50);

 
That would apply 50% transparency to the text box if you put it in the CSS. This would be the same as setting the opacity when it comes to other browsers:
 

opacity:0.5;

 
Here is more information on how to set transparency that will work for the different browsers:
 
http://www.w3schools.com/css/css_image_transparency.asp[^]