No it's no faulty memory. It is working in all other situations when memory is almost full. I can fill it with all the other apps that I use. Only OWB makes these problems.
@ jPV
It also happens when I do not use 68k apps at all. It is definitely OWB. What it says? This one: Failed to allocate 5411766 bytes. Unfortunately, WebKit doesn't check allocations and crashes in such situation. You can either: - Crash - Retry - Quit
I even got this message only because I hit Ctrl+T to open a new tab!