Try correcting DHCP scope in Preferences
Has this problem been fixed for others? I have essentially the same symptoms (I'd be happy to provide my specific configuration details), notably nothing showing up if I type ipconfig under XP. I have upgraded to 5582 and done a clean install (doing all the sudo commands).
I had the same problem after upgrading to Leopard and 5582.
I fixed it (knock on wood !!) by changing the DHCP scope in Parallels-->Preferences-->Network-->DHCP scope.
The default range (or at least, what I found there) is 10.55.211.x but my actual DHCP server (as configured by me) uses 10.0.0.150 through 10.0.0.200. I made that change to Parallels, restarted the VM, and now shared networking is functioning OK. Here is what IPCONFIG shows:
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
C:\Documents and Settings\martinbear>ipconfig/all
Windows IP Configuration
Host Name . . . . . . . . . . . . : martin-winxp
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Parallels Network Adapter
Physical Address. . . . . . . . . : 00-7F-FE-F4-78-B3
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 10.0.0.151
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 10.0.0.1
DHCP Server . . . . . . . . . . . : 10.0.0.1
DNS Servers . . . . . . . . . . . : 10.0.0.1
Lease Obtained. . . . . . . . . . : Sunday, December 09, 2007 14:40:22
Lease Expires . . . . . . . . . . : Sunday, December 16, 2007 14:40:22
... and now for the strange part: the Default Gateway and DHCP Server are wrong (in the sense that on my real, physical network the Gateway is 10.0.0.138 and so is the DHCP server).
... but if Parallels is now happy, then I'm happy.