### Can't get sage-mode to load with emacs 24.2.1

Apologies for a rather newbie question, but I'm just getting started with Sage. I'd like to be able to use it in my favorite editor -- emacs. Sage seems to work just fine; I'm using it from the command line with no problems. But when I attempt to use sage-mode in emacs, I get this error at startup:

Symbol's value as variable is void: sage-command

A little history to show how I got here/replication:
1. Downloaded and installed Sage 5.6 64bit for OSX (running 10.8.2).
2. From within sage, did: install_package('sage-mode').
3. Appeared that sage-mode 0.7 was installed.
4. Started emacs, got this error: "Unknown button type `help-xref'"
5. Looking at threads, saw it might be a problem solved in the new "experimental" version of sage-mode 0.8.
(threads: https://groups.google.com/forum/?fromgroups=#!topic/sage-devel/HufugiDMyFQ)
5. From command line, did: sage -i http://boxen.math.washington.edu/home/iandrus/sage_mode-0.8.spkg
6. Now getting the current error on loading emacs.

My .init file has:
(add-to-list 'load-path "/Applications/sage/local/share/emacs")
(require 'sage "sage")
(setq sage-command "/Applications/sage/sage")

I've tried a number of things at the command-line level (symbolic link to sage file, editing $PATH, editing the $SAGE_ROOT directory, etc), but nothing seems to get me past the current error.

Any help is greatly appreciated.