All 10 Jerry Seinfeld Broadway concerts are sold out. Tickets went on sale 10 AM July 23 and were gone by 3:30 PM, said publicist Merle Frimark's office. Demand for the comedian's Aug. 5-9 one-man Broadway engagement was so great that, before noon, a second phone line had to be created to accommodate incoming calls.

Frimark's office stressed that the reason tickets lasted as long as they did was due to the relatively low-tech, by-phone-only manner in which they were sold. Popular events sold through computerized ticket services often sell out in under an hour.

Seinfeld will hold 10 concerts in all. Each date, from Wednesday, Aug. 5, to Saturday, Aug. 8, will feature two concerts each, at 7 PM and 10 PM. Shows on Sunday, Aug. 9, will be at 5 PM and 9 PM. The latter concert will be broadcast live on HBO. (Doors at the Broadhurst Theatre will close at 8:45 PM sharp.)

Seinfeld will donate his income from the concerts to programs benefiting students in the New York City public schools. The money will be distributed through Public Education Needs Civic Involvement in Learning (PENCIL) and ArtsConnection. Seinfeld is preceding the New York concert series with what may amount to the most far-flung pre-Broadway tour in history. He began with a booking in Australia, where he staged a handful of June performances in Melbourne and Sydney. The globe-trotting comic followed that booking with dates in Sweden (July 3-4), Iceland (July 8-9) and London (July 12).

Warmup gigs are include San Antonio (July 17-19 at the Majestic Theatre), Omaha (July 24-25 at the Orpheum Theatre) and Des Moines (July 31 Aug. 1 at the Civic Center).