define.xml validation: quirk using CLI v. GUI

I have a SAS macro that generates and runs a BAT file to validate define.xml.  It was working fine until a couple of days ago, when it produced an XLS file with the first sheet ("Issue Summary") populated correctly with config file, date, & column headers, but no messages.  Here's the file created by the macro:

@echo off

rem Date-time Friday, April 12, 2013 10:41 AM

rem OpenCDISC version [1.2.1]  Define configuration version [1.0]
rem Output XLS [c:\temp\validateDefineXML_2013_04_12_10_41.xls]

s:
cd S:\Submissions\tools\OpenCDISC\opencdisc-validator-1.2.1\lib
java -Xms256m -Xmx1024m -jar validator-cli-1.2.1.jar -task="Validate" -type="Define" ^
-source="c:\temp\defineTest.xml" ^
-config="S:\Submissions\tools\OpenCDISC\opencdisc-validator-1.2.1\config\config-define-1.0.xml" ^
-report="c:\temp\validateDefineXML_2013_04_12_10_41.xls" ^
-report:overwrite="yes" > "c:\temp\validateDefineXML_2013_04_12_10_41.txt" 2>&1

The thing is, when I use the GUI - version 1.2, 1.21, or 1.3 - on the same input XML I get 7 messages.  GUI v. CLI/BAT is the only difference in execution: OS (Windows XP Pro), Java build (1.5) are the same.  I get the same "die quiet" behavior whether the BAT file runs as an X command from within SAS or whether I run it standalone (i.e., double-click on the BAT file from Windows Explorer).  I've tried running with and without the -X parameters, with and without quotes around the task/type/overwrite parameters, removing the redirection in the last line of the command - all with the same result (XLS with no messages).  There are no errors or warnings in the TXT file:

 Beginning validation, please wait...
 The validation has completed.

We have other macros that validate SDTM datasets in a similar way, and they appear to be working correctly, so I'm at a loss to explain why define.xml validation is failing.