Is this the world's most boring robot or what? I looked them up and all I could find were threads dating from 2005-06.
DoCoMo/2.0 P900i(c100;TB;W24H11) (compatible; ichiro/ mobile goo; +http://search.goo.ne.jp/option/use/sub4/sub4-1/)
Does anyone hereabouts read Japanese? I sure hope the "meta tag" section means "these are the commands we honor" because I found them snuffling around the no-indexed Panda Page one day ;) I don't suppose any amount of Japanese would shed light on that /sub4/ business* though.
They caught my notice recently because they gobbled up six consecutive pages-- plus robots.txt-- in a mere eight minutes. (The first six pages in one directory. They'd picked up the index page a couple days earlier. Did it take the computer two days to decide that there might possibly be something interesting here?) For goo, that counts as a rampage. Normally it's robots.txt, one page, don't see them again for a week.
* They've either got some meticulous rewriting or those are real, physical directories. I navigated back upward one by one.