London-based VoIP firm Cellcrypt has raised an undisclosed sum in second round of VC funding led by Notion Capital, the investment vehicle set up by founders of Messagelab. Stephen Chandler of Notion will join the Cellcrypt board and the investment will go towards further international expansion. The company, which recently opened a US office, offers a high-security, encrypted voice calls through its own technology for Nokia (NYSE: NOK), BlackBerry and Windows Mobile handsets and fixed line phones. Cellcrypt says its services are mainly used by governments, businesses and high-level executives. Release.