Some web sites are not mobile (phone) friendly and memory will indeed run out. This phone starts with 256MB RAM ( http://www.gsmarena.com/blackberry_curve_3g_9300-3422.php ) and then has much less than that free as apps and such eat that up.
Your average PC has 4 to many times that but here's what I'm seeing. Folk want what they get on the PC on the phone. This means the web site has to test with phones.
Bob
"The available memory in your device is very low. Please close some tabs." My Phone's browser always crash with notifying this message. I haven't installed many of application on device and have cleared browser cache but still facing this problem. I am using BB curve9300 3G.

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