Unable to load couchbase dynamic library PHP 5.6

I am unable to get couchbase sdk work with PHP.

I have downloaded the php sdk from github.

I get the following error in php error log when i restart apache:

PHP Warning: PHP Startup: Unable to load dynamic library ‘/usr/lib/php5/20131226/couchbase.so’ - /usr/lib/php5/20131226/couchbase.so: undefined symbol: core_globals_id in Unknown on line 0

Have you also installed libcouchbase? It’s our C SDK. The PHP SDK wraps libcouchbase.