Skype-like Service with similar functions

PHASE 1: I require a Skype-like service which allows the following: - Voice / Video Conferences - Instant Messaging services - One to one conferences to one to many. - File Transfer - Fully Encrypted Communication - Available on Android, Iphone and Blackberry for Mobiles - Available on PC, MACOS for Desktops I was thinking of using Asterix for the SIP Server and Kamailio as the encryption bridge since it is a free Open Source. For the client, I was thinking of using Linphone for desktop and mobile I am open for suggestions to team who has done this kind of project before. Please do not proposed a paid, expensive solution as this is just meant for a small company of less than 30 to communicate. Your charges should mostly entail installation and configurations. PHASE 2: Once the SIP server and Linphone is properly working. I need a team to redesign the Linphone desktop and mobile client as follows: - Unique User GUI - Hardcode the server settings. So new users just needs to enter username and password to start using Looking forward to all bidders