I've been trying out pocket trains... Note quite the same, but it does have better graphics and is run directly by NimbleBit (not Mobage/Dena).
I've actually done it.
Needed to download some applications, and it took a while, but I managed to do it. Followed this guide: Click here if you want to transfer save data!
I'm currently trying out Logis Tycoon Evolution as a replacement hoping for the A re-release. It's not quite perfect - first of all it's not only planes!
All in all, I feel it's fine as a stopgap until hopefully we see the re-release of PocketPlanes on A.