2TheMart.com shares plunged 36% after it said it must raise more cash to complete its already delayed Internet auction site and its outside auditor questioned its ability to continue as a going concern. The Irvine-based company's shares fell $4.25 to close at $7.31 in Nasdaq trading. 2TheMart.com, which once had a market value of $1 billion with promises of a Web site to compete with established auction services such as EBay, said in its first regulatory filing that it had $2.1 million in cash remaining on June 30. It said it still owed IBM Corp. $7.8 million of the $10.3-million cost of developing its site. The company said in January its site was in "final development" and would debut in the second quarter. That sent its shares soaring from $2 on Jan. 13 to $40 a week later. The site's projected completion date is now Oct. 8, according to documents filed with the Securities and Exchange Commission. 2TheMart said in the filing that it lost $1.9 million between Jan. 8, when it began business, and June 30. It had no sales.