Mavenlink, the first cloud based online interactive workplace, has raised an additional $3.9 million in capital from Quest Software and Madden Capital Partners as well as individual angels. The funding will be used to develop new technology and services to upkeep the company’s growing user base of over 100,000 users. The company has raised $5.5 million in total.

Mavenlink helps companies, professionals, employees, and businesses to execute end to end project management working with outside clients, contractors and consultants. Mavenlink cloud based collaboration tools used to manage files and is tightly integrated with Google Apps such as Gmail, Google Docs and Google Calendar.

“The workforce that businesses need today is more flexible than ever. A growing number of telecommuters, freelancers, consultants, and outsourced services are replacing the traditional 9-5,” said Mavenlink CEO Ray Grainger. “We’re committed to providing these virtual teams and project-based workforces with technology that centralizes their information and allows them to work efficiently in the cloud.”

Mavenlink currently has more than 130,000 users and is adding 15,000 new users every month. The company’s collaboration services are one of the top-rated project management apps in the Google Apps Marketplace. The ongoing increase of users’ base reflects as how businesses are leveraging broader array of virtual and collaborative workforce.

“Businesses are leveraging a broader array of subcontractors around the world,” said Grainger. “We want to be the virtual workplace for that virtual workforce.”

The social enterprise movement and cloud based social enterprise applications are gaining momentum. Google recently released Google Plus on Google Apps. Google Apps for Business or the free version of Google Apps customers will get access to the new service if they have already signed up.

Microsoft last month unveiled the availability of a new version of its Microsoft Dynamics CRM services, which now integrates social collaboration tools in the cloud. Salesforce.com has just announced its plans for do.com. Do.com, the hosted project management and collaboration service for small businesses and groups, is the next generation development stack based on HTML5 and a platform-as-a-service.