Django app error

I've made a simple leads-collecting app in Python, under Ubuntu 10.10, using Django as framework and mysql as database and it works perfectly fine. Well, almost perfectly because once in a while it throws some malicious server error when trying to save a new lead. This is my error email:

[Django] Error (EXTERNAL IP): /myapp/save-lead/
...
IOError: request data read error
...
'REQUEST_METHOD': 'POST',
'REQUEST_URI': '/myapp/save-lead/',
'SCRIPT_FILENAME': '/var/www/my_domain_name/myapp/app/app_name.wsgi',

The app already holds 10 000 leads at the moment, but I've received this error 3 开发者_JAVA技巧times now. Where is the problem?