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I found this here in a quick search.

Minimum System Requirements:
Operating System: Mac OS X 10.5.4 (Leopard)
CPU Processor: Intel Core 2 Duo
CPU Speed: 2.0 GHz
Memory: 1 GB RAM
Hard Disk Space: 8.0 GB + 1 GB Swap File
Video Card (ATI): Radeon X1600
Video Card (NVidia): GeForce FX 7300
Video Memory (VRam): 128 MB
Media Required: DVD-ROM
Peripherals: Macintosh mouse and keyboard

Multiplayer Requirements:
Internet (TCP/IP) or LAN (TCP/IP) play supported
Internet plays requires broadband connection

Supported Video cards:
NVIDIA GeForce 7300, 7600, 8600, 8800
NVIDIA GeForce Quadro FX 4500
ATI Radeon X1600, X1900, HD 2400, HD 2600

Recommended System Requirements:
Operating System: Mac OS X 10.5.4
CPU Speed: 2.4 GHz
Video RAM: 256 MB
 
Yes, I've actually done it on one of those Macs, and it works suprisingly well. Keep in mind I did play it at a very low resolution and low-medium quality, thought, and it was still a bit jerky. Better than expected, probably about as smoothly as the Mac versions of Quake 4/Doom 3 at similar settings, which really surprised me.
 
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