unity android dll seg fault signal 11

Hello, I'm working on SQLiteKit C# Dll. I faced numerous problem with android builds. But for beginning describe the situation. I did port of opensource library c#-sqlite for unity and put into dll. now I have situation when that dll perfectly works on iPhone, Web, PC, Mac no single crash, but Android! Android crash the dll with random crash but mostly with SIGN 11, access violation. The most funniest part of this is that if i put source code directly into project - no single problem , no crash, nothing just fine. My question is what is the difference between Android mono and iPhone mono environment why it works on iPhone and doesn't on Android? And one more interest details that is some how depends on Devices , for example My SonyErricson and old Sansung works no problem but Samsung Tab 10.1, and some others do crash?