Remote connection to a SQL Server and getting Unable to connect to server

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http://stackoverflow.com – I got a SQL server running in a Windows server and I got two dedicated server I can connect with success of a IP but of another IP I can't, I tried everything but when I try to connect using the second dedicated server i get this error 'unable to connect'. I'm using mssql_connect function, it's very strange, it looks like this SQL server is blocking this second IP because I can't even connect to this SQL server using telnet in this second IP but in first IP I can connect via telnet and via mssql_connect. Both IPs are Linux Ubuntu. (HowTos)