Loging of postgres requests - Mailing list pgsql-general

I am using a 3rd front end to generate  postgres requests , its reportng
an error with the database.

Is there anyway of loging which sql requests the application is  actual
sending to postgres.  I need to known if the error is being created by
the application generating invalid SQL or if there is a problem with the
desgin of the database tables.

Dave.