Firewall blocks websocket

I don't think that the parenthesis are to blame.
I would rather think that the dynamic port-range allocated by that server disagrees with Vista/7.

For a discussion of the subject, see this article :
The default dynamic port range for TCP/IP has changed in Windows Vista and in Windows Server 2008

To view the dynamic port range on your computer for ipv4, use the following command :

netsh int ipv4 show dynamicport tcp 

To set the dynamic port range for TCP, use for example :

netsh int ipv4 set dynamicport tcp start=1024 num=30000

More commands are described in the above article.

EDIT : Please note that the Windows firewall may be intelligent enough to open a dynamic port specified in the PASV response, even if this port doesn't fall within its default range for dynamic ports. But it may be that it is still not intelligent enough to understand the response without the parentheses. It may pay to have a look at the possibility of extending the default range for dynamic ports.

To open custom port in Windows Firewall, you can do the following:

1. In your Windows Firewall in Control Panel, click on the Advanced Settings option on the left.
2. In the Windows Firewall with Advanced Security window that opens, click on the Inbound Rules on the left.
3. Click on the New Rule on the right side of the window.
4. Select Port on the list of options.
5. Select TCP (or UDP if that is what you require) and Specific local ports, and then write your ports in the text box to the right of Specific local ports (i.e. 1234).
6. Select Allow the connection in the next window.
7. Select the options which you need from Domain, Private, Public (private and public are the network types that you select when you connect to the new network, and windows asks you to select the network type, and domain is obviously your domain).
8. Finally, write a Name and Description in the window that shows next. Click FINISH.

Your port should be now allowed through the Windows Firewall.