The old database handling used [realms]->REALMNAME->database_name to  
specify the pathname for the database.

After the DAL changes, [dbmodules]->dbmodulename->database_name is  
where the db2 backend looks first for the pathname, falling back to  
[realms]->REALMNAME->database_name if it's not found, for backwards  
compatibility, and then falls back to a hard-coded pathname.

The kadm5_config_params handling includes code that looks at [realms]- 
 >REALMNAME->database_name only, and has the same hard-coded default  
pathname.  Some of the code using kadm5_config_params seems to assume  
that the pathname there is correct.

In short, I don't think we currently fully support the mode where the  
database pathname is specified in the dbmodules section only.

Also, for some conceivable database back ends, and in fact for the  
LDAP back end, there may not *be* a filename.  So anything building on  
that filename may need some rethinking.

Ken