The query string length depends on browser. You cannot increase it from your code.
The only solution AFAIK is to find another alternative approach to achieve the functionality.
Depending upon various browsers here are the limits
IE5.0 IE6.0 IE7.0 -->1024 characters
Opera ---> 4050 characters
NetScape6 ---> 2000 characters
NetScape4 --> 30000 Characters
http://www.boutell.com/newfaq/misc/urllength.html[
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