You can change the language to English by replacing all the files in /data/text/english and copying them into the /data/text/japanese folder, overwriting the japanese files.

The game also includes the following languages:

"francais",
"japanese",
"english",
"deutsch",
"italiano",
"espanol"

heres a couple of screenshots i took in the latest iDeaS, lol at "Plactice"