Ted,
Myself and others have been having problems building Inkscape since r17648, when you added the option for the tar-pax format in AM_INIT_AUTOMAKE. Ubuntu Gutsy, which I'm running, and Fedora Core 6, according to some mailing list traffic, don't have a new enough version of automake in their standard repositories to run ./autogen.sh successfully with that option enabled. Other distributions may be involved, too. Using automake1.8 and removing the tar-pax option get ./autogen.sh to work, and I'm wondering what you would think about rolling back the tar-pax option for now, to ease the problems that users of those operating systems are having with building Inkscape, and then re-enabling it later, when the repositories for those distributions upgrade to the newer automake1.10.
Thanks,
John