Anchor links not working in Firefox

I do hope someone might be able to help me. I thought it was just my computer having a funny turn, but I've checked it on another machine and it appears to be a problem.

I have uploaded my new website over the last few days. It works fine, across all browsers, for the most part.

The problem that I am now faced with is that the anchor links that I have on my pages are not actually working. They do not click, and do not link to the page they are supposed to. This is only a problem in Firefox.

Here is an example of the code that it doesn't work with:

<a href="pho1a.php"><img src="images/010.jpg" width=279px height=210px border=0 alt="text"></a>

Oddly, it is also doing the same thing around my text links too, so it is not just a thing with the images.

It is probably something really obvious.

I hope you are able to help.

Thanks in advance.