How to make up :popup as the top-most window?

In the main windows, 10 project names are shown. Each project name is a
link to a popup to show the project detail. Code:

<%= link_to h(project.code), project, :popup =>
[‘detail_window’,‘height=560,width=900,resizable=yes’] %>

This works fine if the user closes the detail window after viewing it.

There is a problem if the user clicks another project without closing
the detail window first. Since the project window is bigger than the
detail windows, the detail window is refresh but it is not the top-most
window.

It seems to the user nothing refresh when clicking different project
(the reality is the popup window is refreshed behind the project
window).

So, how can I set the popup detail windows to be top-most (even it’s
opened before)?

Thanks
horace

p.s. Browser is IE 6