3Com buys Texas Web security company 3Com Corp., the Marlborough maker of computer-networking equipment, said it agreed to buy a Texas maker of antihacker security systems, TippingPoint Technologies Inc., for \$430 million in cash. TippingPoint makes so-called intrusion-prevention systems for businesses, government agencies, colleges and universities, and telecommunications service providers and systems. TippingPoint has 125 employees at its Austin headquarters. The \$47-per-share purchase price offered owners ...