Problem with MS SQL Server 6.0/TTable/Sybase driver

I am having a problem displaying a Microsoft SQL Server 6.0 Text field
when using a particular combination of Delphi controls.

My SQL Database Setup:
Table:  Remarks
Fields: Id, int
        Remarks, text

My Delphi Project Setup:

Table1 Properties:
Active:         False
DatabaseName:   MyDB1 (Sybase alias) or MyDB2 (32 bit ODBC driver
IndexFieldName: Id
TableName:      Remarks

DataSource1 Properties:
DataSet:        Table1

DBMemo1 Properties:
DataField:      Remarks
DataSource:     DataSource1

Sybase Driver Details:
Version:        1.0
Type:           Server
DLL:            SQLD_SS.DLL

Using the above setup, with Table1.DatebaseName set to MyDB1 (the
Sybase driver alias), I change the Table1.Active property to True and
the first remark correctly appears in DBMemo1. If I then double
click the TTable control, the Form1.Table1 Fields window appears. This
window contains a Navigator control. If I choose the Last button,
gibberish appears in DBMemo1. Choosing the Previous button obviously
changes the record but still displays gibberish, until I choose the
First button when the correct data is displayed again.

If I go through the above procedure again but set Table1.DatabaseName
to MyDB2 (the 32 bit ODBC driver alias), everything works fine.

Whats wrong?

Many thanks in advance.
Andy Fawthrop
Softly Aware Limited, Buxton, UK