System.Data.OracleClient requires Oracle client software version 8.1.7 or greater

Yes, they are many resources on the web about this problem, but none helped me. And because I encountered this problem twice and did not remember how I solved it, I thought of posting this, at least as a note to self.
The solutions on web suggest that you are not allowed to read/execute some dlls in the oracle client because rights on that folder are not properly configured. Not the case. Real problem: Missing MSVCR71.dll. Problem with Oracle 10g Instant Client on Vista and Windows 7. Discovered this by using ProcMon to see what my application is searching for in the oracle client folder. The same way I discovered I was missing the Network\admin folder where tnsnames.ora files should be located.

org.ajax4jsf.config.ParsingException: No filter mapping set for a filter

It goes something like this:

ERROR [[/WaSFP]] Exception starting filter richfaces
javax.servlet.ServletException: Error parse web application config

Caused by: org.ajax4jsf.config.ParsingException: No filter mapping set for a filter richfaces
        at org.ajax4jsf.config.WebXMLParser.init(WebXMLParser.java:131)
        at org.ajax4jsf.config.WebXMLParser.init(WebXMLParser.java:199)

It seemed strange, because I had defined a filter mapping and It worked for me before, so why not now? I had something like this in my web.xml:

    <!-- Richfaces configuration-->
    <context-param>
        <param-name>org.richfaces.SKIN</param-name>
        <param-value>blueSky</param-value>
    </context-param>
    <filter>
        <display-name>RichFaces Filter</display-name>
        <filter-name>richfaces</filter-name>
        <filter-class>org.ajax4jsf.Filter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>richfaces</filter-name>
        <servlet-name>Faces Servlet</servlet-name>
        <dispatcher>REQUEST</dispatcher>
        <dispatcher>FORWARD</dispatcher>
        <dispatcher>INCLUDE</dispatcher>
    </filter-mapping>
    <servlet>
        <servlet-name>Faces Config</servlet-name> <!-- wrong, 'Faces Servlet' here-->
        <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>Faces Config</servlet-name>  <!-- wrong again, 'Faces Servlet' here-->
        <url-pattern>*.jsf</url-pattern>
    </servlet-mapping>

Eclipse 3.4 with JBoss tools - Richfaces VPE 3.0.0 CR1. Nerver trust the IDE :)