Forms :: Setting Temporary Default Value For Date / Time Field

My setup:

frmUsedOilContract (contains a header and a subform)
subfrmUsedOilContract (contains a few controls) [datasheet view]

- Removed Date
- Voucher Number
- Building Number

I implemented some code so that a temporary default value could be set for the date and the Voucher Number. I also have the default value for 'txtRemovalDate' set at 'Date()'.

PHP Code:

Private Sub txtVoucherNumber_AfterUpdate()  'Set current value to default value.  
txtVoucherNumber.DefaultValue = txtVoucherNumber.ValueEnd Sub 

PHP Code:

Private Sub txtRemovalDate_AfterUpdate()  'Set current value to default value.  
txtRemovalDate.DefaultValue = txtRemovalDate.ValueEnd Sub 

Also have code so the default value is null when the form is opened.

PHP Code:

Private Sub Form_Open(Cancel As Integer)  'Set Default Value properties to nothing.  
txtVoucherNumber.DefaultValue = vbNullString  txtRemovalDate.DefaultValue = vbNullStringEnd Sub 

This all works great until I try to change the date. If I use the default date (today's date), the new record will stay with today's date. If I change it to a different date, the new record displays a time instead.