title: ClassNotFoundException: com.google.android.finsky.billing.lightpurchase.PurchaseParams
body: <p>I have several apps on the market and iaps are working like a charm. I'm working on a new app right now. </p>
  
  <p>During testing I keep getting an error:  java.lang.ClassNotFoundException: com.google.android.finsky.billing.lightpurchase.PurchaseParams</p>
  
  <p>The app is published on store right now. I had to change the code of iaps due to changes in my app on the side of my server. So now I just sign the changed app with the developer key leaving the version code and name the same. This way the app store thinks this is the published version even when it has different code. I used to do this on all my apps. I make regular purchases to test if it's working.</p>
  
  <p>The purchase goes through fine. I'm being charged for the purchase and I receive an email from the market. The problem is my app should send information to my server in onPurchaseStateChange. But this never happens. Same thing with purchaseResponse. I have a couple lines of code that should be logging information and it's not there. </p>
  
  <p>When I saw this for the first time I tried changing the code. It started working and then stopped again. </p>
  
  <p>All the time I'm getting this error. It does not crash the app and the purchase itself is made.</p>
  
  <p>If anyone knows what's going on please let me know. Thx! </p>