Threading.Lock() question

[Alvin A. Delagon]

I have a multithreaded application that spawns threads which query a 
database server. During stress test I encountered some threads failing 
due "lost connection errors" and sometimes the actual script itself dies 
due to a "Segmentation Fault". I realized that it might be a deadlock 
situation so I applied a lock mechanism but after another stress test, 
some threads are still failing. Here's a rough sketch of my script:

class Process(threading.Thread):
    def __init__(self,lock,query)
       self.lock = lock
       self.query = query
       threading.Thread.__init__(self)
    def run(self):
       ''' Some data processing code here '''
       self.lock.acquire()
       result = cursor.execute(query)
       self.lock.release()

class Send(Request__POA.Send):
       def push(self,query,...some args here):
              lock = threading.Lock()
              Process(lock,query).start()

db = MySQL().connect()
cursor = db.make_cursor()

The class Send is being called by a CORBA client. The script is actually 
a CORBA server which in the future would serve a high traffic of 
requests. Is my usage is locking correct or am I doing something stupid 
in the code? Thanks is advance!