Hanging andriod process on dlopen?

Question

Android

There is an android project using JNI. Inside native code (in c++) dlopen is called. And that's it, on this call (the very first one) the process hangs tightly.
I googled the option with the deadlock of the thread due to the recursive call to dlopen, but my call is not recursive at all: in the static constructor, a native lib is loaded, like System.LoadLibrary("path"), at runtime, a native method is called, which loads several other libraries in turn, so that's not an option.
Another mystery: just recently I built with exactly the same config, and everything worked perfectly. Since then, only the usercode inside the lib has changed, but nothing systemic, new libs have been added either.
Yes, and yet, this is all on an old phone with android 2.2, on a tablet with a quartet and everything was ok, and it remained ok.
Maybe someone has come across something similar?