jQuery Grid Plugin - jqGrid

Hi, I'm very grateful for this useful library.

When I made jqGrid that's read json data from .jsp,  I've met a puzzling problem.

To use pager, Are there any limits of the number of pages ?

My jsp return 33 Columns and 50 rows  from 23404 records on every page.

So, I wanna give a function for paging 469 pages (50 * 469 =  23450 records) to pager.

But, my Grid could only recognize 468 pages.

When pager jump to 469 page, the Grid try to read then abort to move page.

if I make more narrow query, the Grid recognize all of pages.(200pages, 300pages and so)

Of course, the .jsp don't make any error. 

When I give to the Grid a copied .json text that's written by my jsp with over 469 page number,

the grid can read the file properly. 

Are there any hints to solve this problem?

thank you for your help.