I got an assurance from developer this would work with sugar pro 6. Despite the lack of documentation, I configured to best of my knowledge, but richcontact forms submitted via joomla were not being converted to my sugar crm leads.
I contacted the developer and got the following response:
* In RichContact Configuration, please make sure that you have entered your SugarCRM Live Site (URI) correctly. Please don't put / at the end of URI and don't forget www if it is not a sub domain.
* Please check the user information: username and password, they should be correct and the user should exist in SugarCRM.
* There is another possibility when this error occurs. The data returned by SugarCRM server cannot be understood by SOAP, it means PHP cannot return proper XML data back to the SOAP running on your WebSite.
* You need to find with your administrator these types of errors, which stop PHP from functioning and returning proper data back to SOAP. One way to understand what kind of data SOAP expects is to load the following URL into your browser: http://your.sugarcrm.installation/soap.php?wsdl The stuff you see is data that SOAP expects and can understand (it should be a correct XML data).