We have a legacy product that stores dates in the database in 4 seperate columns (century,year,month,day). I've written a function to convert the columns to a date.  When the function is called numerous times using Pervasive's ADO.Net data provider (version 2.10.1.2 or 3.0)  the function fails with an ArgumentOutOfRangeException: Year, Month, and Day parameters descibe an un-representable DateTime. It appears a stack/memory problem but no way to be sure. I've tried the same function using CAST instead of CONVERT, and a number of other changes, but I still get the error. The function appears below. Any help would be greatly appreciated. I'm running workgroup v9.5 sp2 with the latest hotfix.

CREATE FUNCTION TO_SQL_DATE(IN :c tinyint, IN :y tinyint, IN :m tinyint, IN :d tinyint) RETURNS DATE

DECLARE :returnDate DATE;

SET :returnDate = CONVERT(IF(:c = 0 OR :c = 32 OR :m > 12, '0001-01-01', RIGHT(CONVERT(100 + :c, SQL_CHAR), 2) + RIGHT(CONVERT(100 + :y, SQL_CHAR), 2) + '-' + RIGHT(CONVERT(100 + :m, SQL_CHAR), 2) + '-' + RIGHT(CONVERT(100 + :d, SQL_CHAR), 2)), SQL_DATE);

RETURN (:returnDate);

 What's "numerous" mean?  Is it 10, 100,1000, or does it vary? 

I just tried with v10 and ran the function 1000 times with no error.  

It is around 150 typically, assuming that the sql statement contains about 12 calls to the function.  The other thing I neglected to include was that connection pooling is enabled and if you try to re-run the same script even after the connection is closed and re-opened if fails immediately (I assume that's because it is re-using the same pooled connection).  Here is a same sql statement

select
TO_SQL_DATE(Date1C, Date1Y, Date1M, Date1D) as Date1,
TO_SQL_DATE(Date2C, Date2Y, Date2M, Date2D) as Date2,
TO_SQL_DATE(Date3C, Date3Y, Date3M, Date3D) as Date3,
TO_SQL_DATE(Date4C, Date4Y, Date4M, Date4D) as Date4,
TO_SQL_DATE(Date5C, Date5Y, Date5M, Date5D) as Date5,
TO_SQL_DATE(Date6C, Date6Y, Date6M, Date6D) as Date6,
TO_SQL_DATE(Date7C, Date7Y, Date7M, Date7D) as Date7,
TO_SQL_DATE(Date8C, Date8Y, Date8M, Date8D) as Date8,
TO_SQL_DATE(Date9C, Date9Y, Date9M, Date9D) as Date9,
TO_SQL_DATE(Date10C, Date10Y, Date10M, Date10D) as Date10
From SomeTable