I've had this happen a couple of times while processing E6 film. When I hang the film to dry I see a kind of milky fog on the base, either uniform or in stains. But the thing is that when the film dries for a couple of hours (longer that it takes me to get the film dry when this doesn't happen) and the milky substance disappears. Before it dries it's kind of sticky, not much but enough so that I can't slide my finger over film. In other words there's friction. Like I said the whole thing goes away.
I should say that the film was expired. But I've developed many rolls of expired E6 film without this happening. It doesn't seem to affect the image much once it dries, so it's not a problem, but I'd like to know what it is and what causes it. By the way, can really old film mess up your chemicals?