Compare active and disabled text fields in Internet Explorer:
Here’s what they look like in Firefox:
Users won’t be able to tell an active text field from a disabled one in IE. The solution to this problem is pretty simple: CSS. Ask your coder for a tip on how to make a disabled text field look disabled in Internet Explorer.
This sure is a minor issue, but resolving it will help keep users focused before they reach another frustrating point in your interface. :-)