Timepart not showing at midnight

I have a problem showing Oracle TDate's in a DBgrid. The time part is not
displayed at midnight, the 00:00:00 is left out like this:

13-08-1999 23:45:00
13-09-1999
13-09-1999 00:15:00

The DBgrid is connected to a TDataSource which uses a TOracleDataset from
DOA. Same problem with QReports. Same problem also if i use ww-components
from Woll2Woll.

A manual SQL stmt using to_char works like a charm displaying 00:00:00 so I
expect it to be a date to char conversion problem, but im not sure where?

System: Delpi 4 CS sp2, Oracle 8.05, DOA 3.3, NT 4.0 sp3

Thanks
Peter Laursen