Network timeout on Mac OS X 10.6.4 (Snow Leopard)

One of my biggest complaints in earlier versions of Mac OS X (pre-Snow Leopard) was the dreaded network timeout. For example, if I was working on a notebook computer while connected to a networked volume, I could cause a multi-minute timeout (SPOD) for ~2 minutes simply by putting my computer to sleep, disconnecting my network connection, and resuming my session. Eventually, Mac OS would time out and unmount the inaccessible volume, but during that time my machine would be locked up. When Mac OS 10.6 (Snow Leopard) came out it seemed to fix this problem, but lately, I've been experiencing similar network timeouts in Mac OS X 10.6.4 (Snow Leopard). I can reproduce it by doing the following, with 2 machines:

Machine A connected to network via hard-wired ethernet. Machine B connected to network via WiFi.

1. On machine A, mount a volume on machine B via AFP 2. Disconnect from WiFi network on machine B (and disable WiFi) 3. Connect machine B to router via hard-wired ethernet (it gets a different IP address via DHCP)

Machine A will then time out for at least 1-2 minutes (SPOD). When timeout expires, the shared volume is unmounted and my machine becomes responsive again.

Anyone have a fix?