italeffect, yes, i agree with the apparent effect of the issue it presents, however i kind of know where the issue really steams from in the way which leveldb is instantiated during the calls. I can repeat in QT5.3.2 (this wallet QT lib build) and in earlier version of QT build platform independent tests it will take some detective work to nail it down.  QT is now a dying technology for wallet related stuff imho and should be phased out in favor of modern node-gyp toolchain build processes for hybrid native HTML5 apps in due course then soon to be replaced with pure JSX based alternatives.

But in the meantime QT wallets more than provide a flexible and stable, solid platform for cross-platform networked clients..  Who knows maybe soon we will have some kind of "firm" spec. framework setup by a crypto-working group for crypto-related tech developments beyond those of BIP provide to date.. maybe wishful thinking