A mild profits warning from Broderbund Software Inc sent the shares crashing over 20% yesterday, underlining just how fragile and overstretched prices have become. Shares were off $7.375 to close at $23.125 after the company warned its second quarter profits would come in below analysts’ forecasts. The Novato, California-based software company said it expects to report second quarter earnings of between $0.15 and $0.20 a share, excluding charges where Wall Street had been hoping for $0.31 a share. Broderbund said that while unit volume was up over 30% for the quarter, prices were down.