From the MVP site and David Bartosik's FAQ page at:
http://www.publishermvps.com/Default.aspx?tabid=30
Q. How do I make my hyperlink open the URL in a new browser window?
A. Launching a new window is done by using the target attribute of the
link. Publisher does not have any support for this. Meaning there is no way
to code a target when linking within Publisher. The workaround is to use the
HTML Code Fragment feature and code the link yourself, including the desired
target. As such:
To open a new window per target:
<a target="_blank" href="
http://www.domain.com">Link Text</a>
To re-use the window you launched on each target use:
<a target="_display" href="
http://www.domain.com">Link Text</a>
DavidF