init.ora filenames when using 9R2 on Windows OS

I've noticed that init.ora files created in my 9R2 install on Win 2003 have a string of numbers appended to the filename.

For example, init.ora.37200414559 (shows as a 37200414559 file type!!!)

Its easy enough to rename the file to 'init.ora' but what's causing this and can my install be configured to prevent this?

someone renamed it?

I think you get those when you use dbca and it creates an spfile for you and then creates the pfile with that name so you know what went in it. The extra info is the timestamp it was done