400 error after approx 90 request

Hi all ,

I have configured screen-scrapper-2.7.2 basic edition for ezinearticles.com
and its working very fine but after approx 90 to 94 request it starts giving error 400 but whne i check the url on which it started 400 error it was opening fine in browser.

below is result from log for any help:
====================================
Detail Page: Preliminary URL: http://www.ezinearticles.com/?~#IGNORE#~&id=~#ART_ID#~
Detail Page: Resolved URL: http://www.ezinearticles.com/?&id=225912
Detail Page: Sending request.
Detail Page: Processing scripts before all pattern applications.
Detail Page: Extracting data for pattern "Main"
Detail Page: The following data elements were found:
Main--DataRecord 0:
Sub_Cat=Sales
Author=Joshua_Feinberg
Main_Cat=Business
Art_Title=IT Sales Skills: Selling Servers and LANs to Clients
Word_Count=247
Detail Page: Processing scripts after a pattern application.
Processing script: "Write Data"
Writing data to a file.
Detail Page: Processing scripts after all pattern applications.
Articles Listing--DataRecord 4:
ART_ID=226037
Storing this value in a session variable.
Article Title: Processing scripts after a pattern application.
Processing script: "Scrape details page"
Scraping file: "Detail Page"
Detail Page: Preliminary URL: http://www.ezinearticles.com/?~#IGNORE#~&id=~#ART_ID#~
Detail Page: Resolved URL: http://www.ezinearticles.com/?&id=226037
Detail Page: Sending request.
Detail Page: Warning! Received a status code of: 400.
====================================

I am not behind any proxy.please help if any tweak or any idea.
Any help will be appreciated.