href 'return false' and hyperlink states

[newglasses]

I have been charged with using CSS to change the visited state of a hyperlinks that use "return false" in the href to cancel the redirect.

The CSS is simple, the other three states (L, H, A) render properly. The visited state will not.

I am inclined to say that this task is impossible without more JS due to the fact that the click event is effectively cancelled to and the redirect.

Can anyone here concur? Or, am I missing something obvious?

Simple example:
<a class="thumb" href="img/a.jpg" title="Day 1" onclick="showImg(this); return false;">

[clueful]

<a class="thumb" href="img/a.jpg" title="Day 1" onclick="showImg(this); this.className='visitedLink'; return false;">

Where 'visitedLink' is a copy of 'thumb' except with different default attributes.

[newglasses]

Brilliantly simple clueful... I appreciate your reply.