xss_clean on images

[eluser]Seppo[/eluser]
I was checking out the xss_clean on images new feature... and it just doesn't work as expected... out of 16 JPG images I had on my Computer, only 4 passed this test, most of them have a "<?" inside... also lines 754-755 (at revision 1171) says

Code:

* Adobe Photoshop puts XML metadata into JFIF images, including namespacing,
* so we have to allow this for images. -Paul

but it's not useless to allow xmlns if you are not allowing xml (forbidding the use of "<?") so no photoshop / jfif image is accepted, anyway (I tried creating a couple of jfif with photoshop and all had "<?")...
I understand the risks of allowing uploads without XSS clean up, but this functionality, as is, seems to be too much restrictive, up to a level that no site can really use it...

Any thoughts?