If you are and iPhone aficionado, you absolutely want your iPhone to work  on your ShoreTel IPBX! I recently downloaded VeNetCorps SipPhone fromt the iPhone App store! There are several SIP phone apps at the store, but most have a pre-programmed domain name for the sip registration proxy server. If you want to use your own SIP proxy there was no easy way to change the IP address so you had to hack your DNS to get it to point to the ShoreTel SIP proxy. Also you need at least iPhone firmware 2.2 as previous versions had WiFi connectivity challenges that negatively impacted the potential for using a SIP softphone. After the iPhone WiFi acquired an IP address, if you attempted to ping the address you would see latency in excess of 300ms. With version 2.2 this issue has all but become unnoticeable. As with any SIP extension setup on ShoreTel, you need to assign sip extension proxy resources on a ShoreGear switch. In the sites section of the ShoreWare Director, make sure you assign a virtual IP address. This is the address you will use for your “domain’ when you setup the Iphone SipPhone. Clearly you will need a User setup with a SIP phone password defined in the individual user section of the ShoreWare Director. Clearly the assumption here is that you have a WAP that your iPhone can connect to. Also that that wireless connection can route to your ShoreTel network! Once the ShoreTel SIP user, virtual IP address and proxy resources are configured it is time to configure your iPhone SipPhone! After you down load the application and tap to activate the application you will get a screen that lists the options: Dialer, Recent, Contacts, Accounts and Settings. Hit the Accounts tab and you will then EDIT a new SIP account. To get this app to work on ShoreTel you need to enter only three values. First you need to enter the domain name, we have previously defined in the ShoreTel Director as the Virtual IP address. The Username and password are also as specified in the individual user setup in ShoreTel. Hit the DONE tab, and the phone should register and you can make and receive calls from your ShoreTel. I put together a video clip that covers this so you can see that it accutaly works! The video suggests that you enter the user name, but if you want to call the iPhone from a ShoreTel extension, enter the user's extension number instead.  This was just a fun project and latency on the iPhone WiFi is still a challenge for SIP phone usage.  I suspect that Version 3.0 of the iPhone will fix this small issue, but it was a blast trying it out!  Enjoy! Add your iPhone as a ShoreTel SIP extension!