For OGR-NG (supporting OGR-27 and up)
Proxy: Requires build 343 or higher. Build 346 or higher is recommended. Proxies will only receive OGR-NG workunits from an upstream server that is also running build 343 or higher.
Client: Requires v2.9103.509 or later. Clients for Cell and PowerPC require v2.9105.511 or higher. All clients are highly recommended to be v2.9110.519 or higher.
For OGR-NG (supporting OGR-26 and up)
Proxy: Requires build 343 or higher. Proxy build 343 will only receive OGR-NG workunits from an upstream server that is also running build 343 or higher.
Client: Requires v2.9101.507 or later.
For OGR "Classic" (project phase 1)
Proxy: Requires build 311 or higher. However, due to a number of known networking issues in build 311, it is recommended that you upgrade to 313 or higher (if available for your platform).
Client: Requires v2.8009-460 or later. There are a number of client versions earlier than v2.8009-460 that provide the ability to process OGR, however due to known verification bugs in those earlier versions all work computed by them will be discarded by the servers. (Note: OGR may be automatically disabled for non-preemptive operating environments running on lower-end hardware. Details are here:  Why is OGR disabled on my machine?)
For OGRp2 (project phase 2)
Proxy: Requires build 341 or higher. Proxy build 341 will only connect to an upstream server that is also running build 341 or higher.
Client: Requires v2.9008-490 or later.
| 
distributed.net Faq-O-Matic : 
What minimum client and proxy versions are needed for OGR?