@devils_advisor
It is a solution, but not the best solution
. What do you have the "Max. number of connections" set to in the network preferences? This also affects the number of sockets cached for persistent connections.
You can use "shownetstatus tcpsockets" in a shell to show the currently allocated sockets. It smells like a bug in the network card driver to me, which could be falling over if there are too many connections. It could be a bug in IBrowse, but I don't see it on my A1200 with PCMCIA network card + Miami, or on my A1XE with onboard networking.