Looks like it was the JNI cash causing the crash.

Forcing it to look up classes and methods instead of caching them stopped the crashes in the GC.  Will investigate more later.

java/jni/ZT1_jnicache.cpp

@@ -111,7 +111,7 @@ jclass JniCache::findClass(const std::string &name)
 
         jclass cls = (jclass)env->NewGlobalRef(localCls);
 
-        m_classes.insert(std::make_pair(name, cls));
+        //m_classes.insert(std::make_pair(name, cls));
 
         return cls;
     }
@@ -143,7 +143,7 @@ jmethodID JniCache::findMethod(jclass cls, const std::string &methodName, const
             return NULL;
         }
 
-        m_methods.insert(std::make_pair(id, mid));
+        //m_methods.insert(std::make_pair(id, mid));
 
         return mid;
     }
@@ -173,7 +173,7 @@ jmethodID JniCache::findStaticMethod(jclass cls, const std::string &methodName,
             return NULL;
         }
 
-        m_staticMethods.insert(std::make_pair(id, mid));
+        //m_staticMethods.insert(std::make_pair(id, mid));
 
         return mid;
     }
@@ -203,7 +203,7 @@ jfieldID JniCache::findField(jclass cls, const std::string &fieldName, const std
             return NULL;
         }
 
-        m_fields.insert(std::make_pair(id, fid));
+        //m_fields.insert(std::make_pair(id, fid));
 
         return fid;
     }
@@ -233,7 +233,7 @@ jfieldID JniCache::findStaticField(jclass cls, const std::string &fieldName, con
             return NULL;
         }
 
-        m_staticFields.insert(std::make_pair(id, fid));
+        //m_staticFields.insert(std::make_pair(id, fid));
 
         return fid;
     }