[Zope] ZSQL field problem

[Colin Fox]

Hi, All.

I have a form that allows a user to edit a table with a date field.

The user should be able to 'null' the date field.

I'm using a ZSql method similar to this (very simplified):

update sometable
set (birthday = <dtml-sqlvar birthday type="string">)
where
username = 'someuser';

If the user cleared the text input field for the birthday, I'd like to
have it say:
  set birthday = null where username = 'someuser';

But all I get is:
  set birthday = 'None' where username = 'someuser';

Any suggestions?
  Colin

-- 
Colin Fox                                         cfox@cfconsulting.ca
CF Consulting Inc.                                    GPG Fingerprint:
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