I've set VSS client up to use kdiff3 for 3-way merging, which is really useful. But when I use the command-line tool SS.exe, it is just making changes in the file. I'm merging trunk changes into my working branch, and VSS either replaces my branch changes with the trunk version, or marks every change in the branch as a conflict.
VSS won't let me merge into a branch in the IDE so this is my only option, but it doesn't work.