If you have questions about this section, I urge you to email Gabriel M. Elder (gmelder (AT/@/AT) centurytel.net)
Earlier versions of the Medicine HOWTO included a reference to a projectknown as FreeVet, a FOSS package available via QPL, aimed at being such a solution. The project appears to have died after reaching a relativelyhigh level of development and maturity. The only currently accessible information and code that i've been able to find is here: FreeVet