Deleting contents of a Masked TDBEdit?

Can anyone tell me how to delete the contents of a TDBEdit that has
been Masked using a persistent TField? Every time I try to delete
an entry I get a 'EDBEditError Invalid input value' message.

I traced the VCL code into the TCustomMaskEdit.Validate function and
it seems that the logic in Validate does not account for the fact that a
user may want to blank the field. Basically if the character in TDBEdit is not
'type' consistent with the corresponding character in the EditMask then
Validate returns false and the exception is generated. So once you enter a
value and post it the field can never be blanked via your user interface.
It can, however be changed to another 'valid' entry.

Am I overlooking something? I'd prefer not to modify the VCL code.

Any help greatly appreciated!
*  Peter Kott                       Phone :         (908) 805-9213  *
*  PAK Consulting                   EMail :  *
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