Problem installing mysql gem

I’ve been running mysql4 for a while fine, and yesterday updated to
mysql5. Had to reinstall the gem apparently. I followed the
instructions at

to get the patch and everything. All the steps completed without a
hitch, exactly as described on the blog. However when I run gem list,
mysql isn’t included in it. So all the commands ran fine, but gem
apparently isn’t recognizing the mysql gem. I used darwinports to
install mysql, so the only difference in my setup was that I used

sudo /usr/local/bin/ruby extconf.rb install mysql –

as the install command. Any ideas?