The JBoss QE team have been adding Failsafe tests for the Seam modules, if you are running on MacOSX You need to have Firefox installed (it did not work correctly using the firefox 4.0 beta for me) and pass a location of the browser when you run the tests. For me the following maven invocation worked:
mvn verify -Pftest -Dselenium.browser=*firefox /Applications/Firefox_3.6.app/Contents/MacOS/firefox-bin
Locations will probably differ for your machine, but this worked for me.
Confirmed working on 10.6.6 with firefox 3.6 this morning.