possible to use my smart phone with landline?

[sadthai]

i want to use my old (deactivated) android phone with my landline phone connection. anyway this is possible? any device that will connect the android phone with the landline jack using a blue tooth?

im aware that some landline cordless phone has some features like phone to cell link, but this only allows calls from cell phone to be answered through the home cordless phone. remember, i want to answer my landline calls through my smart phone and not the other way around.

you guys may ask why? well, the landline is a business line and in our particular business, it would be a tremendous help if we can save our clients number into our phone's phone book easily. most landland phone has horrible phone book/contact list, and only show call history of 20-50.

porting my landline number to cell service is not an option.

im aware that there are the archos 35 android landline touch screen phone, but i cant find that one for sell anywhere.

thank you for your inputs