It turns out that I actually own the Doonesbury book with that comic in it, so here is a higher quality scan because the online version is so unreadable. It’s not in color, because it was part of a plot, so was printed in the book next to the daily strips it was part of (click for larger image).
Last night I spent nearly 2 hours in the Doonesbury archive looking for a strip which I remember reading when I was just working at IBM. This morning I figured I’d keep going back through the archive on the off chance that it was earlier than I thought, it was. From August 4th, 1996: