Solution for Two PSTN Lines

Hi, I have one BT PSTN line (say Line1) with free minutes to mobiles, so its good for outgoing calls. The other line (say Line2) which i have is acually VoIP but it comes with its own hardware (magicJack if you have heard) so I can’t use a SIP client and have to use the supplied Hw client, but it does give me an option to connect any normal phone to this magicJack (i suppose that would make it a fxs port). Now this magicJack is cheap for other people to call me plus I can take that number anywhere.

I want to find a solution so that all the calls I receive on Line2 get forwarded to my mobile number via Line1. And if I receive any calls on Line1 they should be treated normally (my home phone rings). Does anyone have some idea how I can achieve this with minimal spend? Do I even need Asterisk for this or can this be done using just two ATA (e.g,. SPA3102). Thanx - Atif