WampServer

First, my english is... bad. Sorry.
I have this problem.

I have a local network in my office. I have 2 pc connected with a router and a switch.
I have a public ip that no change when i restart my computer, is the same always (ip fija in spanish).

I have created an user in MySQL with all privileges and password to a bd specifically.

I have a router with the port 3306 open and I stop the firewall when I try to connect to db.

Now the real problem.
When I try to connect to the db in local, no problem, y use php mysql_connect("localhost","user","pass" and it works well.

But when I try to connect to the db from web, from other pc out of my local network, doesnot work. I change in the sentence of php localhost to mi ip address (xxx.xxx.xxx.xxx)

I donot know what to do.

Any idea? Thanks for your time.

Hi.
The error I have is this:
Warning: mysql_connect() [function.mysql-connect]: Can't connect to MySQL server on '213.98.71.190' (10061)