(not) quoting float8 and numeric

Hello again,

I have a problem with Delphi and Postgres (not) working together.

Using the Delphi-Components to acces my tables, I get an error whenever I 
have a float or numeric field.
When updating a record, the generates SQL-Statement does not have the 
values quoted.

I have asked in a Delphi-Newsgroup how/if I can change that.

Just in case it is not possible: Can I tweak Postgres to less picky about 
the quotes?

The query looks like:

UPDATE inv_artikel SET bezeichnung='Asbach Uralt' WHERE nr=1 AND 
bezeichnung='Asbach Uralt' AND gebinde='Flasche' AND inhalt='3 ltr' AND 
anzahl=1 AND preis=81.45 AND gruppe='sp' AND subgruppe='' AND anz=1

---> ERROR:  Unable to identify an operator '=' for types 'numeric' and 
'float8' You will have to retype this query using an explicit cast

Thanks,

Stefan