Script/generate scaffold errors

I’m following the Agile Development With Rails book and having some
trouble. Specifically, I’ve typed:

% ruby script/generate scaffold Product Admin

and received the following error:

symbolize_keys': undefined methodto_sym’ for
#YAML::Syck::MergeKey:0x23b2e48 (NoMethodError)

I’ve got rail 1.1.2 and have done

% sudo gem update rails --include-dependencies

and been told that all is up to date. I’m on OSX 10.4.6 and I’m aware
this can be temperamental, but I’d appreciate any suggestions as to what
might be the problem (given that gems is telling my my installation is


OK, ignore this. I’ve figured it out. DB issues.