Problem in email

Hello
i installed DIreectAdmin VPS now
but when i send email to yahoo, i not recive email in my yahoo emaill
but when i send email to Gmail, i can recive it.

you think what is problem?

my name servers is:
nameserver 8.8.4.4
nameserver 8.8.8.8

Thanks.

oh
it was blocked on yahoo:
[root@host ~]# telnet mta6.am0.yahoodns.net 25
Trying 66.196.118.37...
Connected to mta6.am0.yahoodns.net (66.196.118.37).
Escape character is '^]'.
421 4.7.1 [TS03] All messages from 66.xx.xx.xxx will be permanently deferred; Retrying will NOT succeed. See http://postmaster.yahoo.com/421-ts03.html
Connection closed by foreign host.

how i can remove from yahoo black list?

http://help.yahoo.com/kb/index?page=content&id=SLN3436

might help

You should need to check your software and reinstall again with the instructions.