There are some oversights that just go on for years until someone finally fixes them. That was the case with creating log files on 4D Server. Previously, you had to do a backup, and then quick like a bunny create the log file before there were any changes to the database. This usually meant not letting users login and shutting down 4D's internal web server. It was something you could live with, but it wasn't as elegant as it should have been.
I just noticed a few moments ago that the problem has been resolved (as of 4D 2004.5 or earlier). Now, when you start a log file and the database has been modified since the last backup it asks you if you'd like to backup and have the log file start as soon as the backup completes. This is the way it should be - thank you 4D for making the change.