http://curioustech.home.insightbb.com/xport.html
XPort COM port splitter for Windows XP and Windows Vista.
Compatible with all GPS and Navigation software.
Used by Military, Fire/EMS, Police, and consumers everywhere around the world.
Recommended by Microsoft, USGlobalSat, Pharos, and others.
* Up to 8 virtual, bi-directional ports for simultaneous application usage.
* Optimized to use very little memory. Much smaller than any other solution available.
* Scans and repairs the COM port arbiter to free up unused ports after drivers leave them allocated.
* Scan is only compatible with NMEA 0183 and SiRF Binary protocols, but the splitter handles any form of data transparently as long as it's continuous.
* Fixes most hibernation issues. Any USB device, including hubs can be automatically stopped and restarted when hibernating.