> Create table TemperatureData ( Tempt real, TimeStamp default CURRENT_TIMESTAMP);
> Insert into TempertaureData values( 40.2, NULL);
Try specifying the Tempt field and it's value only. SQLite may be
interpreting the NULL as a supplied value and thus not inserting the default
value.
Insert into TemperatureData (tempt) values(86.0);
Don't have SQLite on the machine here, or I would check it myself.

