From your description I assume you are in Central European Time zone. The date is being stored in the database in GMT, so a date in your timezone of 18 January 2011 00:00:00 is the same as 17 January 2011 23:00:00 in the GMT timezone.
If someone in California were to connect to your server and view this record, they would see the date as 17 January 2011 15:00:00. They are all the same time, just displayed in different timezones linked to the user's regional settings.
So the answer to your question is that yes, if you import the exported data it should display correctly (as 18 January) in your timezone.
If you update to the newest version 2.5.2.1 then this will be resolved. Before the new release I had to use a java parser to set the input date as 2011-01-18 T00:00:00.000