I looked for the error -325 in the documentation, it says:
Filename must be specified with a full path name.
This error occurs if you attempt to create a table using the WITH LOG IN clause but do not specify a complete path to the log file. This error can also occur if you use INFORMIX-SE to create database logging but do not specify the full path of the log file. Make sure to specify a full pathname, including the name of the log file, where the log file will reside.
But it is really strange, untill now I thought, that it's not possible to dedicate a special logfile for a database. Informix has a pool of logfiles and manages these logfiles on it's own.
The dbspacename you specified in your create database statement affects only the default location of the tables and the location of the catalog tables belonging to the specified database. Nothing to do with transaction logs.
If you create a 'Logged database' in IDS (7 and 9), you have to specify 'WITH LOG' in the create database statement. In that case IDS will use the predifined transaction logs, defined per IDS server. You can check see the logs with 'onstat -l'.
In SE, technology was different. SE is a C-Isam file based database. No dbspaces are defined, which means that evey table uses a seperate file. If you want to turn on logging in SE, you must specify 'WITH LOG IN <path+file>'. In that case SE would use this file for the transaction logs. These transaction logs were only used for COMMIT and ROLLBACK.
No point in time restores were possible at that time.