blackberry-webworks/WebWorks-API-Docs — comment on commit dfa3dcca1c940b7b388ab9f7e5b481ea68302ae2
File: api/blackberry_payment.js line 375
By tohman:

If I got it right invocation of callbackOnSuccess only occurs in the positive result (when user has right for this digital good SKU), but if he doesn't have right would callbackOnFailure be invoked or neither of them? In that case user can't be sure that the response is negative.
Similar comment is apply also for isAppWorldInstalledAndAtCorrectVersion method below.