I have emptied the database via phpyadmin, then tried to import campsite_core.sql in the database. This also rendered a error message. Saying that there's a syntax error. :/
Thanks a lot, I will try to see if the manual can provide a solution, but siince I am a noob with mysql maybe it's best if I ask the hoster to resolve the problem. Again, thanks a lot!
Turned out it was an issue with MySQL. Error code 1064 corresponds to a version mismatch. Asked the hoster to update to MySQL 5.1 (from v.5.0) and installation went smooth.