To enable Sybase-DB support configure PHP --with-sybase[=DIR] . DIR is the Sybase home directory, defaults to /home/sybase. To enable Sybase-CT support configure PHP --with-sybase-ct[=DIR] . DIR is the Sybase home directory, defaults to /home/sybase.
As of PHP 5.3.0, the Sybase extension has been superseded by the sybase_ct extension and is no longer maintained. To continue using sybase you must use the sybase_ct extension.