I found there is also a seperate SUEXEC error_log which had this:
[2008-06-28 21:38:54]: uid: (1059/secretar) gid: (1061/1061) cmd: kareha.pl [2008-06-28 21:40:40]: uid: (1059/secretar) gid: (1061/1061) cmd: wakaba.pl
I'm not sure if this is helpful or not.