On Linux, I installed php 5.3.8 from source. Using phpize for installing an extension works fine but not on one specific extension (mysqlnd).

```
# cd /opt/php/5.3.8/ext/pdo && /opt/php/5.3.8/bin/phpize
... this runs ok
# cd /opt/php/5.3.8/ext/mysqlnd && /opt/php/5.3.8/bin/phpize
Cannot find config.m4. 
Make sure that you run '/opt/php/5.3.8/bin/phpize' in the top level source directory of the module`

```

As you can see error can not be that I am not on top level source directory since I am. I tried to call phpize from ext folder - did not work either! For info I have m4 installed

Any idea? Thanks :)