BCD Field and 4 decimal places

  I am using Delphi 5.0 + ADO + MS Sql. I am trying to retrieve a
currency rate which is defined as decimal in the db with scale of 7.
  Since Delphi always create the BCD fields there is round off
Ex : 0.1256475 read as 0.1256
How to avoid this? Any help will be greatly appreciated.