VMWare said today it had reached a deal to acquire Virsto, a maker of software that specializes in optimizing storage in virtual and cloud computing environments. Financial terms were not disclosed. Virsto was founded in 2007 and had raised about $24 million in venture capital funding from August Capital, Canaan Partners, Interwest Partners, Southern Cross Venture Partners and Correlation Ventures. VMWare shares fell more than 2 percent during the day to $77.04 per share.