No WAI check on images on file fields

In the prepackaged demo on the "About us" page I added a new image in a file field and another new image in a big text. I turned on all WAI integrity checks and adequate rule.

Both images do not have any "ALT" value so will cause some WAI errors.

In the case of the image introduced in the big text the error is correctly diagnose. This is not the case for the image in the file field.

There is no reason that one is causing an error and not the other.

Finally How do I enter an alt value for an image field?

[This integrity check was not present in Jahia 5 SP4 so I delayed it for the 6.0 SP1+ - Up to you the urgency of WAI checks]