<textarea></textarea> in the caption possible - without escaping quotes?

Hello,

When I try to put <textarea><img src="URL"/></textarea> as the caption, it automatically escapes the "s and adds \ in front of them. So in the end, when I click on an image: I get a text area with <img src=\"URL\">. That code isn't valid! How can I make it so it doesn't automatically escape the quotes?

I have a good amount of PHP/SQL knowledge, so if it's a complicated process, please don't hold back.

Cheers