The following error is showing up in my httpd log file when trying to execute the PHP extension mdEmailPHPWrapper.so via the mdEmailPHPWrapper.php. I've followed all the instructions and everything loads fine but the extension is not working.

Here is the error:

*** glibc detected *** /usr/sbin/httpd: free(): invalid pointer: 0x00cf7a40 ***
======= Backtrace: =========
/lib/libc.so.6[0x1b26c5]
/lib/libc.so.6(cfree+0x59)[0x1b2b09]
/usr/lib/libstdc++.so.5(_ZdlPv+0x23)[0x3cb7973]
/usr/lib/libstdc++.so.5(_ZdaPv+0x1f)[0x3cb79cf]
/usr/lib/libmdEmail.so(_ZN6cEmailD0Ev+0xf3)[0xccf07f]
/usr/lib/libmdEmail.so(_ZN7mdEmailD1Ev+0x26)[0xcdd3c6]
/usr/lib/php/modules/mdEmailPHPWrapper.so[0x7a0d1a]
/usr/lib/php/modules/mdEmailPHPWrapper.so[0x7a0d4e]
/etc/httpd/modules/libphp5.so[0x120aef3]
/etc/httpd/modules/libphp5.so(zend_hash_del_key_or_index+0x221)[0x1208da1]
/etc/httpd/modules/libphp5.so(_zend_list_delete+0x8a)[0x120b18a]
/etc/httpd/modules/libphp5.so(_zval_dtor_func+0x9a)[0x11fb01a]
/etc/httpd/modules/libphp5.so(_zval_ptr_dtor+0x8c)[0x11edd1c]
/etc/httpd/modules/libphp5.so(zend_hash_destroy+0x47)[0x1208187]
/etc/httpd/modules/libphp5.so(zend_object_std_dtor+0x43)[0x121b183]
/etc/httpd/modules/libphp5.so(zend_objects_free_object_storage+0x22)[0x121b1c2]
/etc/httpd/modules/libphp5.so(zend_objects_store_free_object_storage+0x8b)[0x121f5eb]
/etc/httpd/modules/libphp5.so[0x11edffb]
/etc/httpd/modules/libphp5.so[0x11fb68f]
/etc/httpd/modules/libphp5.so(php_request_shutdown+0x1ba)[0x11a175a]
/etc/httpd/modules/libphp5.so[0x12882af]
/usr/sbin/httpd(ap_run_handler+0x6d)[0x63c60d]
/usr/sbin/httpd(ap_invoke_handler+0x77)[0x63ffc7]
/usr/sbin/httpd(ap_process_request+0x1ae)[0x64c5fe]
/usr/sbin/httpd[0x6492ef]
/usr/sbin/httpd(ap_run_process_connection+0x6d)[0x64488d]
/usr/sbin/httpd(ap_process_connection+0x4c)[0x64498c]
/usr/sbin/httpd[0x651346]
/usr/sbin/httpd[0x651661]
/usr/sbin/httpd[0x65173a]
/usr/sbin/httpd(ap_mpm_run+0xb44)[0x652294]
/usr/sbin/httpd(main+0x96d)[0x62774d]
/lib/libc.so.6(__libc_start_main+0xdc)[0x15ee9c]
/usr/sbin/httpd[0x626751]