The NSA's Diffie-Hellman based Key Exchange Algorithm (KEA) was declassified and published in June 1998 in "SKIPJACK and KEA Algorithm Specifications", version 2.0. I implemented KEA within the framework of Peter Gutmann's encryption toolkit cryptlib. Unfortunately some of the results produced by my implementation differ from the test vectors provided by NIST (see below). I have heard that other independent KEA implementors have encountered similar discrepancies.
On 23 Feb 1999 the NSA responded to my email query about the test vector differences, indicating that NSA is reviewing the KEA specification and may revise it. While I await resolution of the issue, I'm reporting the test vectors from my implementation for purposes of comparison with other implementations.