I've built my project in powerpoint 2003 with presenter 7. My
associate imported a 2003 powerpoint project into office 2007 with
presenter 7 and it didn't work. My assumption is that your way
might work if I created a new project with powerpoint 2007 and
presenter, as opposed to importing an older version of powerpoint.
p.s. This issue is not apparent with presenter 6.2 and in
both powerpoint 2003 & 2007, the mailto link works in
"slideshow"