Assertion failure: (*path != '/') on bzr-svn 0.4.16 / bzr 1.10

$ bzr branch --stacked svn://dev.eclipse.org/svnroot/technology/org.eclipse.vtp
Cloning Subversion repository as branch. To import the individual branches in the repository, use "bzr svn-import".
- [======================== ] generating file id map 140/258^stacking support in bzr-svn is experimental.
Assertion failed: (*path != '/'), function svn_ra_get_file, file subversion/libsvn_ra/ra_loader.c, line 665.
Abort trap (core dumped)

This is on bzr 1.10 and bzr-svn 0.4.16 on MacOS X 10.5.6 using python 2.5. It is reproducible.

Branching as an unstacked repository works fine:

$ bzr branch svn://dev.eclipse.org/svnroot/technology/org.eclipse.vtp
Cloning Subversion repository as branch. To import the individual branches in the repository, use "bzr svn-import".
Branched 258 revision(s).
$