The subversion client that comes with the Gentoo linux distribution, and possibly other distributions, has problems with extremely slow connections to the Rice campus subversion server.
The problem appears to stem from the fact that the Gentoo subversion client is built with a faulty neon library. Upgrading the libneon library to a version 0.29.3 or higher appears to fix the problem.
This may require a rebuild of the libneon library and subversion client software.
Credits
I would like to thank Kenji Takizawa who was instrumental in the testing of this problem and for finding this solution.