[ruby-talk:04021] Ruby and Interbase on Windows

Hi,
why this code doesn't work?
The errore is: "No such file to load -- interbase <loaderror>"
Windows 2000 Prof. platform, Ruby 1.4.5 for Windows, and "interbase.dll"
in c:\ruby
#=====================================================
require 'interbase'
conn = InterBase::connect('c:\ibase\employee.gdb', 'sysdba',
'masterkey')
st = "select * from fornitori"
cursor = conn.execute(st)
cursor.each  do |record|
  p record[0],  "|", record[1], "|", record[2]
end
conn.commit
conn.close
==================================================
Thank you.

jilani