I have the exact same problem! And when I try to "Connect to server" Apple key+K, I get some message about the address not being correct smb:// afp:// and so forth. This is happening when I use an adress like smb://192.168.1.4 cifs://Server or simply ChrisiBook.local. I cannot connect to apple shares either

Did this work for you in 10.5.1? 10.5.2 rev.1?
My connections worked great in 10.4.x, never tried 10.5.x before...

Any help?