php exec() not returning error message in output when executing svn command

[Domloally]

I am trying to get certain output for svn command in XML format. Output is ok when I type valid parameters. However, when I type in wrong password, output does not show error message.This is the PHP code:\[code\]exec('/usr/bin/svn --username something --password something --non-interactive log -r HEAD --xml --verbose http://a51.unfuddle.com/svn/a51_activecollab/', $output);\[/code\]Here is output I get in the terminal:\[code\]<?xml version="1.0"?><log>svn: OPTIONS of 'http://a51.unfuddle.com/svn/a51_activecollab': authorization failed: Could not authenticate to server: rejected Basic challenge (http://a51.unfuddle.com)\[/code\]And here is the output I get from the $output variable with var_dump:\[code\]array(2) {[0]=>string(21) "<?xml version="1.0"?>"[1]=>string(5) "<log>"}\[/code\]As you can see the $output variable does not return third line of output, where terminal does. Please help me to get the same output as I get in terminal (I even tried with shell_exec() or system() methods but they return the same output as exec()) How do I get full output? Thank you in advance!