Pop-up photos not visible on a Mac

[cursor]

I setup a couple of web pages for my father to evaluate and comment on some of his old photos from his earlier years. He uses an Apple Mac. He tells me that when he clicks on a thumbnail, nothing happens. Why might that be?

http://sorenson.worx.cc/nz_pics/index.htm

[ckh]

I can think of a couple possibilities.

Safari isn't updated.

Javascript is disabled.

[MEB]

hello cursor,
I have no ideia what could be wrong... maybe an outdated browser?
I´ve tried the link you provided and everything works fine both in Safari 5 and Firefox 3.6 running on a Macbook with OSX 10.6.3.

[cursor]

Thank you both for your kind replies. I'll have my father investigate the browser version and the javascript activity status.