my ppower4 is Version 0.8.4-7, the latest available for the Mac from fink.sourceforge.net
but actually the problem is clearly not with ppower4, but with the pdf; and the question is, how to find out what is wrong with the pdf. I don't see anything wrong, and my latex installation is completely standard (for Mac OS X), namely a completely up to date TeXShop on top of Gerben Wierda's tetex distribution. But I can patiently await 0.9.3 ...
