A mechanism for providing proxy support for special subtree entries in a directory information tree by defining filters at the proxy level to indicate relationships between main subtree entries and associated special subtree entries. A proxy server receives a request from a client for a special subtree entry and determines whether the distinguished name of the main subtree entry can be built using information in the request and pre-defined relationships between the main subtree entry and the requested subtree entry. If so, the proxy server builds the distinguished name of the main subtree entry associated with the special subtree entry and applies a partitioning filter to the distinguished name of the main subtree entry to determine a target directory server in the plurality of backend directory servers that comprise the special subtree. The proxy server then sends the request to the target directory server.