How come need to get MySQL to work in a strange way?

The following is an error for using RoR with MySQL:

C:\ror\shov17>rake db:migrate
(in C:/ror/shov17)
!!! The bundled mysql.rb driver has been removed from Rails 2.2. Please
the mysql gem and try again: gem install mysql.
rake aborted!
193: %1 is not a valid Win32 application. -

(See full trace by running task with --trace)

C:\ror\shov17>gem update mysql
Updating installed gems
Nothing to update

C:\ror\shov17>gem list mysql

*** LOCAL GEMS ***

mysql (2.8.1 x86-mingw32)