problem with changing logging mode

I have a server with some dbspaces, often when I import a database , I do it without logging and then I change the logging mode to unbuffered with onarchive.That works fine. Recently I have created new dbspaces, and I have imported without logging a database on them. But when I try to change the logging mode with onarchive, it doesn't work, the archive (level 0) containing the new dbspaces ends (completed) but the request to change mode is still pending. I have checked that the database is created in the archived dbspaces. Moreover, I created 2 databases ( 1 table, 1 field) without logging, the first in a old dbspace, the second in a new one. I requested both to change logging mode to unbuffered and I archived (level 0) both dbspaces, the first database turned its logging mode, the second did not. There was no error message. I can see the logging change for the first database in ONLINE.LOG , nothing for the second one. I created the new dbspaces the same way than before: onspaces -c -d name -o offset -s size -p dev I can't see any difference between these new dbspaces and the others. Before the creation of these new dbspaces, I change the configuration of the server: I create a dbspace for the physical log and I put it in. I set ONDBSPACEDOWN to 2. Thanks for all ideas. Ronald.