Geesh -- I obviously didn't read your question well before posting an answer, did I? Please forgive me -- allow me to blame it on painpills I was taking two weeks ago.. haha
Anyway, I can still help.
My logs report the date in 24 hr time and it works great -- I archive logs back for a few years.
Are you sure your wusage configuration file is working correctly?
The wusage configuration file that you're using to run the reports needs to point at all the directory/folders that are holding your log files. Maybe you have it pointing at just one file.
Another thing to check is your NES. Do you roll the logs over at midnight every night? Mine save to the same directory, but they don't get deleted.
It kinda sounds like your configuration file only looks at the access or errors log file, and not anything else that might be in the same folder/directory like access.08Dec-12AM
Let me know if you want me to post more comments.... :-)
Good luck,
Melissa