To what extent is Garry's Mod and its dedicated server software multi-threaded?

[FredWPx]

While everybody is wondering how amazing the next Half-Life game from Valve will look, I'm rather more interested in the performance really.

Garry's Mod, both to the client and server software, can be extremely demanding when it comes down to processing power.

But I've recently found out that the dedicated server software is only capable of consuming the power of one core on the processor?

Is this true? If so, how much attention is being put on entirely multi-threading both client and server software?

[Coon]

Servers use one thread for processing networking and one thread for everything else, if I remember right.

[editline]6th September 2011[/editline]

Although you can also used host_thread_mode to force multithreading, but the majority of things will still not be multithreaded.