Bug 177091 Can't access stored procedure defined in Oracle Package
1.setup an oracle connection 2.try to call a stored procedure defined in package
data/org.eclipse.birt.report.data.oda.jdbc.ui/src/org/eclipse/birt/report/data/oda/jdbc/ui/editors/SQLDataSetEditorPage.java
* 
	 */
	protected void populateSchemaList( )
	{
		if ( rootNode != null )
		{
			removeTreeItem( rootNode );
		}
		if ( JdbcPlugin.getDefault( )
				.getPluginPreferences( )
				.getString( DateSetPreferencePage.SCHEMAS_PREFETCH_CONFIG )
				.equals( ENABLED ) )
		{
			getAvailableSchema( );
		}
		else
		{
			getSpecificSchema( schemaCombo.getText( ).trim( ) );
		}
		
		
		if ( schemaCombo.getItemCount( ) < 1 )
		{
			schemaCombo.add( JdbcPlugin.getResourceString( "tablepage.text.All" ) );
			schemaCombo.select( 0 );
			if ( schemaList != null )
			{
				Iterator it = schemaList.iterator( );
				while ( it.hasNext( ) )
					schemaCombo.add( it.next( ).toString( ) );