ColdFusion 8 and ODBC Drivers

I have installed CF 8 Standard Edition and Oracle 11g. I used an Oracle ODBC dsn to connect to the database. But I get this error when I try to execute an Oracle stored proc.: [HY000] [Macromedia][SequeLink JDBC Driver]Network problem, session aborted due to internal error in remote procedure call, connection closed. Example: <cftry> <!-- this is executed without problems --> <cfquery name="set_role" datasource="#Session.AppDSN#"> SET ROLE role_web IDENTIFIED BY xxx; </cfquery> <!-- this one fails --> <cfstoredproc procedure="safcown.SAFC.sel_parametro" datasource="#Session.AppDSN#">    <cfprocresult name="qry_param"> </cfstoredproc> <cfcatch type="database">   <cfoutput>#cfcatch.detail#</cfoutput>   <cfabort> </cfcatch> </cftry> This sp is very simple: select * from table. I would be grateful if you could help me. Thanks in advance.