ADO and Oracle- Trouble executing stored procedures

[Norby mahoney]

I'm using ADO against an Oracle 10g database.

2 problems:
1.) calling the following stored procedures throws an exception on the last line in the code below (DB_E_ERRORSINCOMMAND; IDispatch error #3092):

	ADODB::_CommandPtr pCommand;  // Stored Procs
	ADODB::_RecordsetPtr recordSet;

	pDBConn.CreateInstance( __uuidof( ADODB::Connection ) );
	_bstr_t connectString = GetConnectString();
	pDBConn->Open( connectString, "", "", 0);

	pCommand.CreateInstance(__uuidof(ADODB::Command));
	pCommand->ActiveConnection = pDBConn;
	pCommand->CommandType = ADODB::adCmdStoredProc;
	pCommand->CommandText = _bstr_t("sp_getcard");

	VARIANT vCardNum;
	vCardNum.vt = VT_BSTR;
	vCardNum.bstrVal =  _bstr_t( "100" );

pCommand->Parameters->Append(pCommand->CreateParameter(_bstr_t("CardNum"),ADODB::adVarChar,ADODB::adParamInput,50,vCardNum));
	recordSet = pCommand->Execute( NULL, NULL,ADODB::adCmdStoredProc);

This procedure compiles within Oracle; the examples I've seen on the web lead me to believe that my approach should work. Can anyone help or direct me any ADO + Oracle (not ADO.NET) sites that may shed light on this.

Here's the actual Stored Proc:

( CardNum IN VARCHAR2, RC1 IN OUT Omwb_emulation.globalPkg.RCT1)AS BEGIN OPEN RC1 FOR SELECT LastName, FirstName, CardNumber, UserDate FROM Addresses WHERE CardNumber = CardNum; END sp_getcard;