Date Validation Error

Question

I'm currently using the DD-MON-YYYY format for my program. The item is for a Date of Birth, and I'm using a date picker to get the information. The problem I'm running into is that If someone types a date into the box (say 2/2/2009) instead of using the date picker, it is throwing an invalid month error (I'll come back to that part in a minute). My first question is this, is there anyway to set a Date Picker item to not allow people to type into it so that they HAVE to use the selector?
If that's not possible, then it brings up the other problem that I brought up. The invalid month error. I believe that what's causing the problem is my validation. I'm running a check to make sure that the DAte of Birth does not occur in the future. To do this, I'm running a PL/SQL Returns Boolean script. This script runs, and runs correctly, if the date picker is used to input the date, but if you type in the date using a different format, then it throws the error. The code that I'm using is this:
DECLARE
WHO DATE;
HOW DATE;
BEGIN
HOW := SYSDATE;
WHO := :P3_DATE_OF_BIRTH;
IF WHO > HOW
THEN
RETURN FALSE;
ELSE
RETURN TRUE;
END IF;
END;
Any help in pointing out what I'm missing in why the code isn't runnig correctly is more than greatly appreciated. Thanks.
Josh

Answer 1

Thanks for all of the input. The way I have the validations setup is that I have three just for the date field. The first checks if it is null or not, the second checks whether it is a valid date (using the option in Apex itself), and the third one checks whether it occurs in the past or not. The thing is that it is hitting the future check and giving me an invalid date error (I tried putting in gggggg as the date, and it somehow got past the valid date validation.) and threw the invalid date error on the future check. I don't know if this changes anything or not, but I'm certainly not giving up yet.