default log handler

[Andrea Zagli <azagli libero it>]

is there a way to set a log handler for every log domain my app uses,  
without knowing them?

for example if my application uses libgda, i can know the log domain  
looking inside source code; but if libgda use other libraries that i  
don't know, how can i set a log handler for these?

of course the solution is to search which libraries my app uses, but i  
want to create a single function that works for every apps

and i don't want make this search every time a library is updated to  
look if it has changed the log domain or it uses a new library, etc.

thanks in advance