[PATCH] Derby-157 Patch, plus 2 other minor server fixes.

[Army <qo...@sbcglobal.net>]

Attached is a patch that does the following three (pretty minor) things:

1) First and foremost, it resolves DERBY-157.  If a datetime string that is not recognized by the server is received 
from the client, the server will now catch the resultant Java exception and throw a valid SQLException with SQLSTATE 
22007 ("The syntax of the string representation of a datetime value is incorrect").  The old behavior was to throw a 
DRDA protocol exception and deallocate the connection.

2) It corrects a small problem in the way the server treats timestamp strings.  This problem, like DERBY-157, only 
happens with non-JCC clients: users who insert a timestamp value into a Derby table by binding a _string_ value (ex. 
"1948-04-08 02:24:48") to a _timestamp_ parameter will actually get a different value back when they do a SELECT because 
the value is 'warped' by the server before insertion.  In particular, extra 0's are added to the end of the string--ex. 
"1948-04-08 02:24:48000"--which are then treated as seconds when the server calls java.sql.Timestamp.valueOf(), and thus 
the wrong value is inserted.

This doesn't happen with JDBC drivers because the code in question is only executed when a _string_ value is being bound 
to a _Timestamp_ parameter--basically, the user would have to do something like

ps.setTimestamp(1, "1948-04-08 02:24:48")

--but JDBC doesn't allow that, because the second argument has to be a Timestamp object.  With an ODBC client, though, 
this kind of thing is possible, and so this problem should be fixed.

3) It removes an extraneous call to "finalizeChain()" that was introduced as part of the "Multiple EXCSAT fix" patch 
(see http://mail-archives.eu.apache.org/mod_mbox/db-derby-dev/200501.mbox/%3c41EF3DC3.6030407@Sourcery.Org%3e).  This 
extra call doesn't lead to any bad behavior, but since it is unnecessary and technically incorrect, it's good to remove 
it.  It's a simple one-line removal, so if no one minds, I figure it can be made with this patch, since all of the 
changes in this patch are to the same file and they are all pretty minor.

In terms of tests, I haven't modified or added any test cases because these are problems that can only be seen with a 
non-Java driver--and as far as I know, the current Derby test harness has no means of introducing such a driver.

I have run the derbynetmats suite (on Windows using jdk142) with these very minor changes and all tests passed.

Committers, please commit when you can...

Thanks,
Army