hosts.deny blocking incoming emails?

[jackop]

I modified host.allow and hosts.deny to stop outgoing spamming.
hosts.allow > ALL: somedomains someip
hosts.deny > ALL: ALL

However, it seems to be blocking normal incoming emails as well.
Now I can send emails out, but I was told others can't send
emails to me. They got denial messages whey they tried that.

Are there anything wrong with the hosts.allow and hosts.deny?
How can I modify the files to allow incoming emails?
Thanks for your help in advance.