As have the entire 4.5.x releases. I think OEM support first began with 4.2 and the 3D overrides. Newer releases have added compatibility for new retail and OEM cards as well as some previously retail only features creeping over to support OEM. 4.5.5 adds Versavision support to all Radeon cards (OEM or Retail) which have the necessary hardware support to handle it (Radeon 8500 and up) as well as 3D overrides and VV support for the X850 XT and I think the iMac G5s with Radeon 9600s.