You need he 4.0 beta file.
PS3 Theme Builder 2.5 Full Install – Install first
PS3 Theme Builder 3.0 Upgrade – Install this upgrade after installing the above 2.5 version.
PS3 Theme Builder 4.0 Beta 2 – After installing both versions above you’ll need to extract this package into the install directory for the 2.5 & 3.0 versions and overwrite files when asked to.
Heres the file http://www.lili-chan.com/4.0_Beta_2.zip