WordPress MU

1. How can I programatically determine where my error log is?
1a. If that's impossible, where is it by default?

2. I can't approve comments. I select some comments, set the strip-box to approve, and click approve. The script hangs at "waiting for mywpblog.net" - forever. If I refresh the page, the comments are not approved. This behavior is similar to a behavior I encountered when I tried to install wordpress.

Any advice on either problem is appreciated.

your error logs depend on the OS yo r server is running on and if you're on shared hosting I am not sure you'll have access to them. some control panels give you access, so what control panel are you using?

And often WP/WPMU will place a file called error_log in whatever folder it's getting the errors in.

Have you asked your host?

Also, if you've had this script-hanging issue with single WP, and again in WPMU, it may be a server issue.