Internet security firm V-One Corp, which floated on Nasdaq last October, warned yesterday that its second quarter revenues would be considerably below expectations at about $2.1m, against $1.4m in the same period a year ago. The Rockville, Maryland company offers an integrated security package comprising smart card, firewalls and encryption technology. First Call estimates quarterly losses of $0.03. V-One said the market had not matured as quickly as it had hoped, but that it had won contracts to earn it substantial revenues in the third quarter and beyond. The company cut the scale of its IPO back at the last minute and offered 3.3 million shares at $5 each. And after rising through January, they are now at their lowest point so far, closing at $3.75 yesterday.