rx ring buffer sizes cannot be modified with ethtool on be2net network interfaces

Issue

When attempting to modify the receive (rx) ring buffer size on a be2net network interface with the ethtool utility, an error message is displayed

> [root@server ~]\# ethtool -G eth0 rx 512  
> Cannot set device ring parameters: Operation not supported

Is it not possible to modify the rx ring buffer size with be2net network interfaces?