undefined index error

Getting these errors repeatedly on running update.php
Drupal version: 7.13 dev

Notice: Undefined index: similarterms in blockcache_alter_block_info_alter() (line 107 of /ebs/www/html/sites/all/modules/blockcache_alter/blockcache_alter.module).
Warning: Invalid argument supplied for foreach() in blockcache_alter_block_info_alter() (line 107 of /ebs/www/html/sites/all/modules/blockcache_alter/blockcache_alter.module).

http://screencast.com/t/G60DxcVppeea