This patch fixes it:

20c20
< echo "*** Testing for error conditions ***\n";
---
> echo "*** Testing for error conditions ***".PHP_EOL;
22a23
> 
23a25
> 
29c31
< echo "\n--- Done ---";
---
> echo PHP_EOL.PHP_EOL."--- Done ---";
44,46c46,48
< resource(%d) of type (stream)
< 'abc.txt' is not recognized as an internal or external command,
< operable program or batch file.
---
> 
> Warning: popen(abc.txt,rw): Invalid argument in %s on line %d
> bool(false)
57c59,61
< --- Done ---
---
> 
> --- Done ---'abc.txt' is not recognized as an internal or external command,
> operable program or batch file.

This patch passes on PHP5.3.11rc1 on Windows 7 sp1x64.

It does not break for me on Linux x64 (Gentoo and Fedora 16) with PHP5.3.11rc1.

This bug has been fixed in SVN.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.

 For Windows:

http://windows.php.net/snapshots/
 
Thank you for the report, and for helping us make PHP better.