Yes, the long arm of Windows Server 2003 SP2 is still being rectified and this should do it as far as the networking problems are concerned. FYI – Q is aka Eriq Neale, author of SBS Unleashed.
Microsoft released KB948496 which is an update that disables ALL of the Scalable Networking components that were added into Windows Server 2003 SP2 last year. The previous update only disabled two of the four components, and in practice, systems have continued to have problems when any of the Scalable Networking components were enabled.
This update could come down with Automatic Updates this month, but may not get automatically installed. If you are running SBS 2003 with Windows Server 2003 SP2, you need to install this update.