I need to add a behavior to one of the links on our Sharepoint web page.
Basically when a user clicks the link - a pop up dialog box will appear alerting
the visitor about legal issues.

Our site is built on a certain template and I can easily add this behavior if I
create the page in Designer and apply the template...but it seems that once I
save the page - the user will need Designer to edit it? Is there any way
possible to maintain editing via the browser while still adding one behavior to
a link? i also tried creating the page within sharepoint but the Designer will
not allow me to open it outside of the sharepoint browser editor.

We cannot provide Designer to the end user and our department doesn't want to be
responsible for on-goig edits.