[Sage] Install Sage 1.3.6 doesn't

[R.Irwin]

Dear Sage folk,
       Sage won't install to Firefox1.8.0.1 the most recent download. 
I've entered the sage.mozdev web address in exceptions for installing 
under Tools> Options> Content several times. It's on the list of 
exceptions now but no go. It doesn't matter whether ' warn when websites 
try to install ' is checked or Popup blocker on or off.  I would like to 
install Sage. Rob Irwin