Commented by: @alexpotapchenko

It is not a bug of ODBC driver, It is ADO trouble.
ADO transfers ftDateTime parameter into SQLBindParameter (ODBC driver level) as SQL_C_TYPE_DATE in this case.

You need the following code:
with Parameters.AddParameter do
begin
Name := 'MyTime';
DataType := ftString;
Value := FormatDateTime('yyyy-mm-dd hh:nn:ss', now);
end;

Commented by: Ľubomír Herda (lubomir)

The bug is in ADODB unit (adodb.pas).

Solution: Replace original code by fixed code (search all "Fix" word in text).

...
DataTypeValues: array[TDataType] of TOleEnum = (
adEmpty, adVarChar, adSmallint, adInteger, adUnsignedSmallint,
// Orig adBoolean, adDouble, adDouble, adCurrency, adDate, adDate,
adBoolean, adDouble, adCurrency, adDouble, adDBDate, adDBTime, // Fix
adDate, adBinary, adVarBinary, adInteger, adLongVarBinary,
adLongVarChar, adLongVarBinary, adLongVarBinary, adLongVarBinary,
adLongVarBinary, adLongVarBinary, adEmpty, adChar, adVarWChar, adBigInt,
adEmpty, adEmpty, adEmpty, adEmpty, adEmpty, adEmpty, adVariant,
// Orig adIUnknown, adIDispatch, adGuid, adEmpty, adEmpty
adIUnknown, adIDispatch, adGuid, adDBTimeStamp, adEmpty // Fix
);
...
function ADOTypeToFieldType(const ADOType: DataTypeEnum; EnableBCD: Boolean = True): TFieldType;
begin
case ADOType of
adEmpty: Result := ftUnknown;
adTinyInt, adSmallInt: Result := ftSmallint;
adError, adInteger, adUnsignedInt: Result := ftInteger;
adBigInt, adUnsignedBigInt: Result := ftLargeInt;
adUnsignedTinyInt, adUnsignedSmallInt: Result := ftWord;
adSingle, adDouble: Result := ftFloat;
adCurrency: Result := ftBCD;
adBoolean: Result := ftBoolean;
adDBDate: Result := ftDate;
adDBTime: Result := ftTime;
// Orig adDate, adDBTimeStamp, adFileTime, adDBFileTime: Result := ftDateTime;
adDate, adFileTime, adDBFileTime: Result := ftDateTime; // Fix
adChar: Result := ftFixedChar;
adVarChar: Result := ftString;
adBSTR, adWChar, adVarWChar: Result := ftWideString;
adLongVarChar, adLongVarWChar: Result := ftMemo;
adLongVarBinary: Result := ftBlob;
adBinary: Result := ftBytes;
adVarBinary: Result := ftVarBytes;
adChapter: Result := ftDataSet;
adPropVariant, adVariant: Result := ftVariant;
adIUnknown: Result := ftInterface;
adIDispatch: Result := ftIDispatch;
adGUID: Result := ftGUID;
adDBTimeStamp: Result := ftTimeStamp; // Fix
adDecimal, adNumeric, adVarNumeric:
if EnableBCD then Result := ftBCD
else Result := ftFloat;
else
Result := ftUnknown;
end;
end;
...
function FieldTypeToADOType(const FieldType: TFieldType): DataTypeEnum;
begin
case FieldType of
ftUnknown: Result := adEmpty;
ftString, ftWideString: Result := adVarChar;
ftSmallint: Result := adSmallint;
ftInteger, ftAutoInc: Result := adInteger;
ftWord: Result := adUnsignedSmallInt;
ftBoolean: Result := adBoolean;
ftFloat: Result := adDouble;
ftCurrency, ftBCD: Result := adCurrency;
ftDate: Result := adDBDate;
ftTime: Result := adDBTime;
// Orig ftDateTime: Result := adDBTimeStamp;
ftDateTime: Result := adDate; // Fix
ftBytes: Result := adBinary;
ftVarBytes: Result := adVarBinary;
ftMemo: Result := adLongVarChar;
ftBlob, ftGraphic..ftTypedBinary: Result := adLongVarBinary;
ftFixedChar: Result := adChar;
ftLargeint: Result := adBigInt;
ftVariant: Result := adVariant;
ftInterface: Result := adIUnknown;
ftIDispatch: Result := adIDispatch;
ftGuid: Result := adGUID;
ftTimeStamp: Result := adDBTimeStamp; // Fix
else
DatabaseErrorFmt(SNoMatchingADOType, [FieldTypeNames[FieldType]]);
Result := adEmpty;
end;
end;
...
procedure AddFieldDef(F: Field; FieldDefs: TFieldDefs);
var
FieldType: TFieldType;
FieldDef: TFieldDef;
I: Integer;
FName: string;
FSize: Integer;
FPrecision: Integer;
begin
FieldType := ADOTypeToFieldType(F.Type_, EnableBCD);
if FieldType <> ftUnknown then
begin
FSize := 0;
FPrecision := 0;
FieldDef := FieldDefs.AddFieldDef;
with FieldDef do
begin
FieldNo := FieldDefs.Count;
I := 0;
FName := http://F.Name;
while (FName = '') or (FieldDefs.IndexOf(FName) >= 0) do
begin
Inc(I);
if http://F.Name = '' then
FName := Format('COLUMN%d', [I]) else { Do not localize }
FName := Format('%s_%d', [http://F.Name, I]);
end;
Name := FName;
if (F.Type_ = adNumeric) and (F.NumericScale = 0) and
(F.Precision < 10) then
FieldType := ftInteger;
case FieldType of
ftString, ftWideString, ftBytes, ftVarBytes, ftFixedChar:
FSize := F.DefinedSize;
ftBCD:
begin
FPrecision := F.Precision;
FSize := ShortInt(F.NumericScale);
if FSize < 0 then FSize := 4;
end;
ftInteger:
if HasAutoIncProp and (F.Properties[SIsAutoInc].Value = True) then
FieldType := ftAutoInc;
ftTimeStamp:
FieldType := ftDateTime; // Fix
ftGuid:
FSize := 38;
end;

    if \(\(adFldRowID and F\.Attributes\) <\> 0\) then
       Attributes := Attributes \+ \[faHiddenCol\];
    if \(\(adFldFixed and F\.Attributes\) <\> 0\) then
       Attributes := Attributes \+ \[faFixed\];
    if \(\(\(adFldUpdatable\+adFldUnknownUpdatable\) and F\.Attributes\) = 0\) or
       \(FieldType = ftAutoInc\) then
      Attributes := Attributes \+ \[faReadOnly\];
    DataType := FieldType;
    Size := FSize;
    Precision := FPrecision;
    if \(DataType = ftDataSet\) and \(Fields\.Count = 0\) then
      ObjectView := True;
  end;
end;

end;
...