Problem with the conection

I have problem with the conection to my database postgres.
I have no problem with the conection in my server (150.xxx.xxx.xxx) and in
the computers with ip near my server. For example if my server
ip is 150.111.111.111 I can connect with 150.111.111.222 or 150.111.111.113

I connect using the following code:
try{
Class.forName("org.postgresql.Driver").newInstance();
return
DriverManager.getConnection("jdbc:postgresql://150.xxx.xxx.xxx/database?charSet=LATIN1",
user,password);
}
catch(ClassNotFoundException e){
}

The problem happens when I try to connect with the java program to my
server in a computer with 161.x.x.x ip.
In the log file I find this message.

Mar 11 11:42:01 ec3 kernel: SFW2-INext-ACC-TCP IN=eth0 OUT=
MAC=00:30:48:70:1f:e9:00:07:0d:b7:64:00:08:00 SRC=161.xxx.xxx.xxx
DST=150.xxx.xxx.xxx LEN=48 TOS=0x00 PREC=0x00 TTL=116 ID=30787 DF
PROTO=TCP SPT=1708 DPT=5432 WINDOW=65535 RES=0x00 SYN URGP=0 OPT
(0204056401010402)

In the computer with ip 161.xxx.xxx.xxx they open port 5432 (for using
postgres) and I include this lines in the pg_hba.conf file

host database user 150.111.111.111 255.255.255.255 trust
host database user 150.111.111.222 255.255.255.255 trust
host database user 161.xxx.xxx.xxx 255.255.255.255 trust

Can someone help me with this problem?
Thanks.

MJ