It's been a while... since I last played with SQL Server 2000

Ok here is a simple problem: I want to assign a value to a column at insertion time.

TABLE:

ID int indentity
DH_Creation datetime default Getdate()
QuartID int (FK to the Quart table)
....

I have a UDF named GetQuartID(@TRX_datetime), that returns an integer based on the passed argument (in this case, another column (DH_Creation) will be the argument)

How do I bind this default to the column ??? I tried in the design window to add this default to the column: dbo.GetQuartID(DH_Creation) but it doesn't seems to be valid...

How do you that ?

Thanks.