Using RadGrid Binder Inside HTML Tag

Hello all,

My post on Stack Overflow hasn't gotten any love, so I'm giving the forums a go! I'm trying to use the RadGrid Data Binding syntax within a Sitefinity widget control designer. My goal is to take a given Image URL and use it as the "src" attribute of an <img> HTML tag:

<span><img src="ImageUrl" /></span>

 I already have the data-binding all set up and going. Other properties are correctly data-bound, and even ImageUrl works when it's not within an HTML tag. However, whenever it is in an HTML tag as it is above, no data-binding takes place (The image's "src" attribute reads as "ImageUrl"). A more complete snippet, containing the entire "sf:FlatSelector" tag, can be found on PasteBin.

Everything works with the exception of the ImageUrl data-binding. Any help would be appreciated!