Openfire server : Exceeding the maximum number of online users

Hi,

After surfing the web and reading the openfire scalability, I found that I could have more than 50,000 users online and chatting at the same time.

My problem is that I am not able to reach more than ~9,000 users online, and when this maximum is exceeded the server disconnect some clients in order to connect the new one.

Note that my openfire server is installed on a windows server with the below specifications.

So my question is as follows... Can I really reach more than 50,000 active users ? and If the answer is yes, how can I achieve it, and what are the specifications of my server ?

Server Specifications :

Microsoft Windows Server 2008 R2 Standard

Intel(R) Xeon(R) CPU L5640  @ 2.27GHz, 2266 Mhz, 4 Core(s), 4 Logical

4GB Ram

Thanks in advance.