Mac to PC connection problem


I use a cross over ethernet cable to connect my iBook with
my iMac (both running OS X) wich works perfectly fine. But, if try to connect my ThinkPad (Win95) to the iMac the same way, all I can do is ping between the computers. No ftp,http or telnet. Only ICMP. If I start up the iMac in Classic mode (9.1) and start filesharing and NetPresenz it's the same thing. It works fine from the iBook but not from the ThinkPad. I've verifyed the ThinkPad's
networking capabilities without any problems on my corporate network.
What could be wrong here?

Mans Langert
Yes, I've set up the PC the same way as the iBook with fixed IP, same mask and so on. I mean it works from the iBook but not from the PC, so the setup in the iMac must be ok. From the iBook I can connect via http, ftp and telnet.
I don't use Samba, Sharity or Dave.
If I can use icmp why can I use , howcome I can't
ftp or http? It seem like IP works fine but not TCP, right?