As an "out of the box" solution a title (kind of tooltip) with an area or image can be used, together with the link plugin. See more details in our WIki:
http://www.megazine3.de/doc/Title
http://www.megazine3.de/doc/Area
http://www.megazine3.de/doc/Links#url
http://www.megazine3.de/doc/Overlays

The tool-tip will show up on mouse over, and a link (i.e. an URL) can be assigned to an area, overlay or title, which gets activated on mouse-click. This offers one link per element, and the link is not a text in the tool tip/pop up box, but assigned to the area or image. Like a linked image in HTML.

There is an additional options which will offer more flexibility: writing a plugin with ActionScript3.
Such a plugin could be based on an existing plugin like the "overlay" plugin, since "overlay" already supports mouse over detection.