Look at the file header.
If you're on a unix box,
Go to $AP_TOP/admin/sql.
Enter more apacmaib.pls.
On our system, the results look like
REM +==================================================================+
REM | Copyright (c) 1999 Oracle Corporation
REM | Redwood Shores, California, USA
REM | All rights reserved.
REM +==================================================================+
REM | Name
REM | apacmaib.pls
REM |
REM | Description - Package AP_ACCOUNTING_MAIN_PKG
REM | The package contains accounting entry generic procedures and functions
REM | used for accounting entry validation, inserting into accounting entry
REM | header and lines.
REM |
REM | History
REM | Created By: Jayanta Bhowmik (03/31/99)
REM |
REM +==================================================================+
SET VERIFY OFF
WHENEVER SQLERROR EXIT FAILURE ROLLBACK
CREATE OR REPLACE PACKAGE BODY AP_ACCOUNTING_MAIN_PKG AS
/* $Header: apacmaib.pls 115.17 99/09/02 16:01:46 porting ship $ */
From this, I can see we're using version 115.17, and the package being created is AP_ACCOUNTING_MAIN_PKG.
Had I known the package that was being created, I could have also tried
SELECT text FROM all_source
WHERE name = 'AP_ACCOUNTING_MAIN_PKG'
AND line < 10
AND type = 'PACKAGE';