Asterisk small office setup

We currently have a Switchvox AA65 in our office. We want to replace the switchvox system entirely with an open source VoIP system. We expect all parts of the VoIP system to be actively maintained by the developers (e.g. Asterisk or FreeSWITCH, /not/ trixbox). We have a dedicated Internet connection strictly for VoIP, no landlines, 11 Aastra phones and less than 10 DIDs. You will be provided remote access to a dedicated freshly installed Linux server. Your job is to configure the VoIP system and either provide simple instructions to configure for Aastra's (providing support if needed on configuration) or set up some way for the Aastra's to automatically configure themselves (e.g. a TFTP server) Required features: Support up to 15 Aastra 9133 SIP phones, each with its own extension Support our Linksys-based analog-to-VoIP adapter for the office speakerphone Interface to our existing VoIP provider (SIP) Send all voicemails as email to designated email addresses, one per extension Using CallerID on incoming calls, automatically query our remotely hosted instance of SugarCRM Pro and display contact information for a logged-in user of the system Have /either/: - a clearly documented, understandable command line system for configuration - an authenticated web-based GUI for configuration The ability to easily blacklist calls based on incoming CallerID Music on hold via mp3s Provide documentation for setting up future Aastra phones as well as adding new DIDs Nice to have but not required: Email to fax IVR Runs on Ubuntu Conference calling If you are selected, I will need to speak with at least one reference whom you have set up a similar system prior to finalizing the job.