Internet telephony startup Ribbit announced today that one of its long-standing proof of concept projects is now available: an integration with Salesforce.com's on-demand customer relationship management applications. Ribbit-handled voice messages can now be integrated with Salesforce in various ways, including having them converted to text, and much more. While there is proof of concept behind this integration for Ribbit and its commercial efforts, there is also proof of concept here for open source developers who have their eyes on the growing synergies between online telephony and open source.