ok, pywallet works well to get the privkeys from wallet a, but unfortunately it is not designed to work with wallets with versions later than 32500, so when I try to import into a new wallet, the wallet gets corrupted.

So, I am very close, and I like this bulk import/export method because I can prune this giant wallet I have, but I am at a loss how to import the addresses.  The new client has the importprivkey function, but it takes 1-2 minutes per address to import.

Does anyone know a way to import privkeys into a wallet quickly?