Lightbox/Thickbox announcement plugins won’t work

Greetings to the community!

I need to put an announcement on my website and have been looking for a plugin that would allow me to display the announcement in a lightbox/thickbox over site content. Surprisingly three plugins that suit my needs most just won’t work for me. Thickbox announcement, WP Super Popup and PlatinumPopup Lite get installed with no problems at all, let me edit the announcement, Thickbox shows me a wonderful preview, but no popups are actually displayed on the site. I’ve played with the settings for ages, still nothing.

I’m using WordPress version 2.9.2 and my own theme with wp_head() and wp_footer() calls present.

Any suggestions what the problem can be?

Thanks!