FLOTSAM AND JETSAM: Peter E. Parisi's latest effort may not be as free-form as his previous radio show, but at least he's on the air. Parisi is on WEW (770 AM),playing gems from his obscure music collection from 7-10:30 p.m. on Tuesdays and Thursdays and from 6-10:30 p.m. on Sundays. Examples include "I'm Coming Virginia," recorded by Bing Crosby in 1927, and some ditty called "The Okay Laughing Record," cut in 1917. Parisi takes hours off the air to plan and record the show on high-fidelity VCR tapes. This has kept him from doing his video work, which is now in reruns at 10 p.m. Fridays and Saturdays on city cable (but just on Fridays in the burbs). He promises new video stuff eventually.... Riverport Amphitheatre isn't a theme park for adolescents maybe it's a theme park for the arrested-development, middle-aged-adolescent crowd but it has a curfew anyway. Paul Simon recently announced as much to the crowd, and though it seems laughable that the graying bourgeoisie have to get to their SUVs by 11:30 p.m. so they can wait an hour to get off the parking lot, it's true. The Maryland Heights curfew for those under 17 is midnight on weekends and 11 p.m. Monday-Thursday. So if 16-year-old Junior has the car and Lenny Kravitz plays too long, look out for the gendarmes.... Work began recently on the new city jail, some 25 years after the federal court ruled the current one is overcrowded and antiquated. As work begins on the jail, anyone with an eye for more evidence that it's a mad, mad, mad world has only to look across 11th Street at the new, Taj Mahal-ish federal courthouse, where work has stopped because of a dispute with the contractor. As with the long-delayed city jail or the stalled federal courthouse, close enough for government work is measured in years, if not decades.