It seems the JIT compiler has not fully been implemented on PPC. Therefore, it is necessary to compile with --with-engine=intrp on PPC. Otherwise, kaffe will not work.
I talked with Dalibor Topic and this configure option should indeed be used on ppc. I will apply this to the ebuild but leave this bug open for the ppc team to provide their opinion.
It seems that 1.1.5 is keyworded -ppc. I will assign this to the ppc team to test 1.1.6 which I will be adding shortly and maybe readd the ppc keyword.
Tested 1.1.6, this seems to work, good job. :) Marked ~ppc and closing the bug.