Create second instance of mysqld on windows xp
=> only set my_ibt.ini  in the pateh C:\RailsInstaller\
=> my_xxx.ini

[mysqld_xxx]
#if already installed then use that basedir
basedir = "C:\RailsInstaller\MYSQL"

#where you want to set your database
datadir="C:\RailsInstaller\MYSQL\data"
port = 43307
enable-named-pipe
socket = mypipe1


In the command promt which runs as administrator go to
\MYSQL\bin>
And run Command :

mysqld --install mysqld_xxx --defaults-file=C:\RailsInstaller\my_xxx.ini

Service successfully installed.

Then :

net start mysqld_xxx

The mysqld_ibt service is starting.
The mysqld_ibt service was started successfully.