Blank page after activating WPML and PHP Error “allowed memory size exhausted”

Hi, i just buy WPML plugin and installed it with boldial theme. On admin page, after activate the plugin, i’m getting a blank page. And when i check my error_log, i got these message:

[Fri Oct 31 15:03:35 2014] [error] [client ***.***.***.***] PHP Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 30720 bytes) in /var/www_virtual/dynamiclabs.my/public_html/clients/teraju/wp-admin/includes/template.php on line 347, referer: https://clients.dynamiclabs.my/teraju/wp-admin/themes.php

What should i do? Thanks.