Also, how expierenced are you with this BB? The .180 upgrade was heaven sent compared to the .151. The only reason I ask is the same reason s.k. mentioned. There are many culprits that could hinder the operation of your BB.
Get rid of your bears, before it's too late! But, seriously, lag comes from many places, and as it's been hinted, we need more data to help you with your problem to help you fix it.
I'm sure you know this, and I'm not saying it to be an a hole, but if you goto a website in the bb browser, hit menu and close instead of the end button to free up some ram. Opera- menu exit, this program takes tons of ram if you leave it open. Close google maps when you get to your destination. Delete texts after you get about 1000 or so. Typical stuff like that. Almost Everytime you get lag its because your running low on memory.
Blackberry hindered these with large roms and small internal memory capacity dedicated as ram
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