Does it support utf-8?Does it support connection with a pos system?
Yes, VMConnector supports UTF-8 even more because Joomla 1.5.x versions + Virtuemart 1.1x versions are using UTF-8 by default.
VMConnector is a set of Webservices functions on the server side which connects to Virtuemart application framework and enables you to connect from any PC, Macintosh or server to its web services functions.
The particularity of Web services functions is the interoperability, not only for VMConnector but for all Web services functions as it is an industry standard .
In short, you can connect any program to these web services functions using regular HTTP or HTTPS protocol, this enables you to integrate applications through the Web, a Web site being one possible application.
We wrote a free open source vb.net client (VMCClient) which does one possible integration between Virtuemart and MS Excel spreadsheet which can be replaced by any database.

