[slypher]

PhoneAlarm can do it, but I believe it does it based on GPS location not cell location.

http://www.pocketmax.net/phoneAlarm.html

phoneAlarm Key Features

• Provides repeating alarms on new SMS, Email, missed calls, voice messages & reminders
• 10 Custom Phone profiles with manual and automatic switching.
• Automatic profile change based on time, location, Appointment type/category, network and power/ActiveSync events
• Custom Email / SMS alarms based on text, sender or priority
• Alarm notification on weak battery and phone signal
• Customise sound, volume and options for each alarm type in each profile
• Automatically mute system and phone volume
• Skinnable user interface (How to create skins)
• Bluetooth and Flight mode control via profiles (also for Widcomm/Broadcomm stack)
• 1-hand skin navigation and quick-dialer for last 10 numbers
• Gestures supported on skin
• Icons provide direct access to Inbox, call history etc.
• Task-switcher pop-up to close running applications
• Weather plugin with 4 day forecast
• Full dual SIMsupport (needs a v2.0 skin for all features)
• English, German, French, Italian, Spanish, Danish, Norwegian, Swedish, Dutch, Czech, Polish, Greek, Hungarian, Russian, Japanese and Chinese user interface
• Fully supports VGA display and square screen devices
• Optimised for fast performance and maximum platform support
• Simple installation

-s