broken compatability between 1.3.5 and 1.4.1

[Sam Hartman]

we committed to an ABI for Unix, Mac and windows around 1.2.5.

If you have an application using only symbols from that ABI (symbols
defined in our header files without KRB5_PRIVATE defined) we would
consider it a serious bug if such an application failed to link
against 1.4.1 libraries when built against 1.3.5 libraries.

I know of one exception to this: AIX.  I believe it possible to make a
library that would support both 1.4.1 and 1.3.5 on AIX, but you'd need
to be a bit of a wizard to do it.