nfs issue

Hi All,

I have a weird issue with nfs server.
I can export some ips but no others, i have, for example 10.3.1.0/24 so
if i do
exportfs -o async,no_root_squash,rw 10.3.1.0/255.255.255.0:/home
it hangs and i have no answer.
So to get rid of it (had to run servers after a power failure) i did
same command but ip by ip, that worked, but when i try some other ip,
like 10.0.4.2 i have no luck.
Im running Suse 9.0 with kernel 2.4.21.

If anyone can give me a clue...

Tnx and Regards.