I've just upgraded my OS to Mountain Lion and PECL is no longer working (it's on a test drive so no drama, but I'd like to get it working so I can upgrade the OS on my shiny new SSD as well).

I'm using the native PHP installation, no macports/homebrew or anything like that.

Running sudo pecl install uploadprogress (for example) produces the following terminal output:

downloading uploadprogress-1.0.3.1.tgz ...
Starting to download uploadprogress-1.0.3.1.tgz (9,040 bytes)
.....done: 9,040 bytes
4 source files, building
running: phpize
grep: /usr/include/php/main/php.h: No such file or directory
grep: /usr/include/php/Zend/zend_modules.h: No such file or directory
grep: /usr/include/php/Zend/zend_extensions.h: No such file or directory
Configuring for:
PHP Api Version:
Zend Module Api No:
Zend Extension Api No:
autom4te: need GNU m4 1.4 or later: /usr/bin/m4
ERROR: `phpize' failed

I'm guessing the problem is the 3 grep lines. I've found several threads that suggest this is caused by XCode not being installed...but XCode is installed, and updated to the latest version (4.4). All the relevant symlinks to /Developer/usr/bin/* also exist as they should.

m4 is currently at version: m4 (GNU M4) 1.4.13, so even though the output above contains a line pertaining to it, I don't think that can be the problem.

I'm sure it's just a simple issue, anyone got any clues?