I have installed windows 2003 server standard edition SP2 on a Lenovo ThinkCentre M58 7360 machine. In device manager under Other Devices I have PCI Serial Port, PCI Simple Communications Controller, and Unknown Device.
I have downloaded and installed the updated BIOS, Audio, Core Chipset, Parallel PCI Card, Modem, and Networking drivers. These drivers can be found at http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-70942
Upon researching the Vendor and Device IDs I found that the Serial Port was part of Intel Active Management Technology. I was able to install the driver for this but the serial port is still not working.
Vendor and Device IDs
PCI Serial Port - VEN_8086&DEV_2e17
PCI Simple Communications Controller - VEN_8086&DEV_2e14