how important is 'valid html'?  Is there a browser that this causes problems
with? 

I have no problem with fixing this (in general) but I am not keen on
undertaking
this unless there is a pressing need for it.  Otherwise it will happen slowly
over time I guess.  But if you want to do it ... :) ... fill your boots ...

I just did a quick search, there are 68 occurances of <img in chameleon/htdocs
(including php_utils/src), not all of which would require changing ... so it is
not a monumental task.

Note that Button.php does add an alt tag so it would only be widgets that use
images directly that would be a concern (mainly in popups I guess).

Bart, if this is important to you, I would suggest that you start adding the alt
tags as you run across them missing.  I'll do the same.  We'll do a review in a
couple of months and see if we've got them all.

Okay, good idea, will do so.