Currently the version of tpm-emulator within the portage tree is at 0.5.1. The current developers version is 0.7.2. The current ebuild _may _ not have a maintainer at present. Reproducible: Always
Note that 0.5.1 cannot build the kernel module on linux >= 2.6.38 anymore due to the missed ioctl -> unlocked_ioctl conversion.
Added, please see if it actually works.