In Lib/distutils/util.py in the get_platform() function there's OS 
specific code to create a string which describes the current platform. 
This usually includes the OS + version + arch. 

FreeBSD specific code is missing from this function. Currently 
get_platform() returns a string specific to the security patch level of 
freebsd. For example:

freebsd-7.2-RELEASE-p3-i386

This results in eggs that only work on a specific patch level release of 
FreeBSD and are not portable between (for example) 7.2-RELEASE-p2 and 
7.2-RELEASE-p3.

However FreeBSD is actually binary compatible within a major version 
number. For example 7.1 and 7.2 are binary compatible.

This patch adds freebsd specific code to get_platform() after which it 
will return a string like:

freebsd-7-i386