We're seeing this kind of issue:
$ (cd repo1; chg --cwd ../repo2 -R .) chg: abort: too many redirections. Please make sure $path/hg is not a wrapper which changes sensitive environment variables before executing hg. If you have to use a wrapper, wrap chg instead of hg. 
chgserver is interpreting -R as relative to its cwd, instead of
relative to --cwd like regular hg does, which I think causes an
inconsistency leading to the above.