i may be totally under-thinking this, but a really brief and crude thought...just bypass your normal routines, if it's a bot.(I'm assuming, you probably want to do less work on them anyways.)...and just split it into two sections. Bots and Not-Bots.

if ($ENV{'HTTP_USER_AGENT'}=~/^googlebot\/2\.1|slurp|some_other_bot_na
+me$/){

#put any other routines you want to run on the request -> like logs, e
+tc here or just...

print "Location: "http:\/\/www\.example\.org\/$ENV{'PATH_INFO'}";
}

# And if not in your bot-list, do what you originally planned...

else{
your original script's body here
}
[download]

it probably be easier to use the whole googlebot\2.1 stuff in a $variable associated with some array - than putting too many | or statements into that regex... but i'm being lazy and non-thinking at the moment.

one word of caution before using something like this-> any and all $ENV variables need to be cleaned up; One needs to ensure that they have no evil characters in them. As a thought for the directories you have there: $ENV{'PATH_INFO'}=~/^([a-zA-Z_0-9]+\/?)*$/

one can't rely on the $ENVironmental variables too much, but in this case, it probably would work.