PEAR Blog: PHP 5.3 Windows and PEAR (go-pear.phar)
The PEAR blog has a quick note for users of PHP 5.3 and Windows:
Some users have reported that the windows builds of PHP 5.3 are not able to open the shipped go-pear.phar file.
If this is your situation, you can use their workaround (run the distributed phar version) or grab the non-pharred version.