cannot alter column data type to "date"

Below is the message I receive when I try to alter the data type of
a column to "date". I had to drop the column and add it again just
so I can set its data type to "date". How do I change a column's
data type to "date" without dropping and then creating it again?

Hoping for a kind response. Thank you.

SQL error:


ERROR:  column "date_signed" cannot be cast to type "date"

In statement:
ALTER TABLE "canvass" ALTER COLUMN "date_signed" TYPE date


--
_______________________________________________

Search for businesses by name, location, or phone number.  -Lycos Yellow Pages

http://r.lycos.com/r/yp_emailfooter/http://yellowpages.lycos.com/default.asp?SRC=lycos10