The Sempai/Kohai relationship is touched upon during the movie, however there were a couple of problems. In Japan, "Sempai" is often used as an address and as a show of respect to one's superior. "Kohai", on the other hand, can be considered offensive when used to address someone directly, as it is "putting someone in their place." Hence Sean Connery's character effectively insults Wesley Snipes' character throughout the movie. Given that Connery's character is supposed to be well versed in Japanese customs, this action should be taken very seriously. "Kohai" is normally used as a reference, not an address. For example: Wesley is the Kohai of Sean.
In the scene at the country club, the advice that Senator Morton tells the detectives is "If the battle can't be won, don't fight it". That quote is from the book "The Art of War" by Sun Tzu. Wesley Snipes would star in the 2000 film The Art of War (2000) based on that book.
Both MicroCon representatives have played characters in Seinfed at one point or another. Rick (Peter Crombie) played the part of crazy Joe Davola in several episodes, and Greg (Sam Lloyd) played the part of Ricky (Cigar Store Indian).