Can't add insert link on an inline picture

I'm using IMCE to add pictures inline, and I noticed that no one can add a link to a picture, except the admin. I checked all through the permissions, but I couldn't find one that I might have missed.
What I want is to have all authenticated users to be able to click an inline image they inserted using the IMCE feature, then click the 'Insert/edit link' button to add a link.