JDBC & MSSQL seem to be truncating large fields

Question

I'm using jython 2.2.1, and jdbc 1.2 and connecting to a mssql 2000 database, writing the contents of an email to it. When I get to the body of the email which can be quite large sometimes I need to truncate the data at 5000 chars. Except mssql & jdbc gang up on me like school yard bullies, when i check the database loads of my data is missing, every time, with max chars = 256 chars.

I have checked the size of the field and it is set to 5000. what gives?

I am pretty sure it is related to jdbc, as the previous version used .... vb6 & odbc, without a hitch.

here is some code:

BODY_FIELD_DATABASE=5000

def _execute_insert(self):
    try:
        self._stmt=self._con.prepareStatement(\
            "INSERT INTO EmailHdr (EntryID, MailSubject, MailFrom, MailTo, MailReceive, MailSent, AttachNo, MailBody)\
             VALUES (?, ?, ?, ?, ?, ?, ?, cast(? as varchar (" + str(BODY_FIELD_DATABASE) + ")))")
        self._stmt.setString(1,self._emailEntryId)
        self._stmt.setString(2,self._subject)
        self._stmt.setString(3,self._fromWho)
        self._stmt.setString(4,self._toWho)
        self._stmt.setString(5,self._emailRecv)
        self._stmt.setString(6,self._emailSent)
        self._stmt.setString(7,str(int(self._attachmentCount) + 1))
        self._stmt.setString(8,self._format_email_body()) 
        self._stmt.execute()
        self._prepare_inserting_attachment_data()
        self._insert_attachment_data()
    except:
        raise

def _format_email_body(self):
    if not self._emailBody:
        return " "
    if len(self._emailBody) > BODY_FIELD_DATABASE:
        return self._clean_body(self._emailBody[:BODY_FIELD_DATABASE])
    else:
        return self._clean_body(self._emailBody)

def _clean_body(self,dirty):
    '''used to clean =20 occurrence in email body that contains chinese characters
       http://en.wikipedia.org/wiki/Quoted-printable'''
    dirty=str(dirty)
    return dirty.replace(r"=20","")

Answer 1

Deleted my answer - it was totally wrong. Keeping it here though so comments & conversation hang around.

EDIT:

As you can read in the comments, here's what happened:

The data was being put into the database fine, but the MSSQL Query Manager could not display the Chinese characters.