[squid-users] Blocking sites on IP address

hi
i've blocked sites by their names , but i'm still able to access sites
using their IP address. I want to block that also.Any hints!!

thanx in advance
aditya

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			Aditya Raghunath
		INFORMATION PROCESSING CENTER
			BITS, PILANI
		     RAJASTHAN - 333031
		Email: aditya@bits-pilani.ac.in
		aditya_raghunath@yahoo.com
		Phone: (91) - (159) 7645073 Ext 292/317(O)
		       (91) - (159) 7642574(R)    	
		Fax:   (91) - (159) 7644183
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