To add any remaining accounts you have using the old Blogger accounts,choose Blogger(Old) from the drop-down menu under Site Settings/Site Information, then click Add Site. Enter username, password and your categories(separated by commas) Click Finished.
FOR THOSE USING THE RAW FORMAT EDITOR use the following syntax:
blogger_old,username,password
or
blogger_old,username,password,blog_1_id,blog_2_id
You will need to change this line when your account is upgraded to the new Blogger account through Google.