[NTG-pdftex] different rendering of pdftex-generated document in AR4 and AR7

Hi! i'm reporting a problem (found not by me). consider this document: ===================================== \documentclass{article} \usepackage{color} \begin{document} \makebox[2cm][r]{c}\hspace{-2cm}ab \makebox[2cm][r]{c}\hspace{-2cm}a\textcolor{red}{b} \end{document} ===================================== when processed with pdflatex, the generated PDF file is rendered differently by Acrobat Reader 4 and 7 - see the attached files acro4.png and acro7.png. Acrobat 4's rendering seems to be buggy, but i wonder whether it is a real bug in Acrobat 4 or it is caused by a buggy PDF generated by pdftex? Best, v.