[plt-dev] logging getting disabled in DrScheme

I've tried to narrow this down as much as possible. I first witnessed it 
last night on my Mac and I'm able to reproduce it on my WinXP machine 
too. Here's how to reproduce:

1. Create a module:

#lang scheme/base
(log-debug "hello, world")

2. Save it in some file.
3. Open the file in DrScheme.
4. View | Show Log
5. Run
6. Close the file in DrScheme.
7. Open the file again in DrScheme.
8. View | Show Log
9. Run

Now all logging appears to have been inadvertently disabled. For 
example, try doing (log-debug "hello?") at the REPL and nothing happens.

Thanks,
Dave