You can use the following (depending on your source file):
Each converter creates importable QIF files for all account types and Quicken versions.
In CSV2QIF during the conversion enter the account NAME as you have in Quicken. In FIXMYQIF and QFX2QIF enter the account NAME after you loaded the file on the Account Mapping tab.
In Quicken, select File->Import->QIF, browse for just saved QIF file and select "All accounts" from the account dropdown list.
Please feel to email if you need any help. Please tell me more if you are using windows or mac and which file format is your source file.