Setting date fields in mysql queries

I have the following line in a program I'm working on: $query = "UPDATE countertable SET CurrDate = '$ndate' WHERE ID = $id" $ndate is a properly formated date read from a text field on a form on the previous page. When I run the query using mysql_query, it returns TRUE each time, but the field is not updated. The only explanation I can think of is that there is something wrong with the date value. I've echoed it to the screen and it looks fine, but the query still doesn't work. Any suggestions? Thanks in advance, Brad