ModSecurity complains when generating more than 50 nodes

I tried to create 150 page and story nodes with ModSecurity enabled. I received this error message in the browser.

An error has occurred.
Please continue to the error page

An AJAX HTTP error occurred. HTTP Result Code: 501 Debugging information follows. Path: /batch?render=overlay&id=2&op=do StatusText: Method Not Implemented ResponseText: 501 Method Not Implemented Method Not Implemented POST to /batch not supported.

and I received this error message in the apache error_log

[Thu Jan 21 11:12:55 2010] [error] [client 4.9.7.2] ModSecurity: Access denied with code 501 (phase 2). Match of "rx (?:^(?:application\\\\/x-www-form-urlencoded(?:;(?:\\\\s?charset\\\\s?=\\\\s?[\\\\w\\\\d\\\\-]{1,18})?)??$|multipart/form-data;)|text/xml)" against "REQUEST_HEADERS:Content-Type" required. [file "/etc/apache2/modsecurity_crs/modsecurity_crs_30_http_policy.conf"] [line "69"] [id "960010"] [msg "Request content type is not allowed by policy"] [severity "WARNING"] [tag "POLICY/ENCODING_NOT_ALLOWED"] [hostname "d7sandbox.domain.com"] [uri "/batch"] [unique_id "@dNGdc-ASakAACBNSDIAAAAG"]

I have run into this error in d6 as well, but neglected to report it.

The option to disable ModSecurity is not available to me on my host.