Berkeley DB v4.8 Dependency

[myfirst]

A few OS's have deprecated or have begun to deprecate Berkeley DB v4.8 and it's becoming more and more difficult to satisfy this dependency for Bitcoin and derived altcoins.

I understand that it is possible to use a newer version of BDB but with the loss of wallet.dat portability.

However, I'm not sure what this means in regards to 'upgrading' existing installations to a new BDB version.  Will my existing wallet.dat files become damaged or un-unusable if I were to recompile Bitcoin using say for example BDB 6.x?

What are the 'official' plans from Bitcoin's development team in regards to this?
What is the recommendation for someone who may keep a number of wallet.dat files for Bitcoin and several Altcoins.

[lclc]

Check this Pull Request: https://github.com/bitcoin/bitcoin/pull/5686

[altcoinex]

Please see https://github.com/bitcoin/bitcoin/issues/3971 and https://bitcointalk.org/index.php?topic=502482.0