Importer support for migrated passwords

Hi all. I am trying to migrate a forum from discuz x to discourse (v2.0.0.beta4), but running the corresponding import script results

creating users
1 / 242 ( 0.4%) /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activemodel-5.1.4/lib/active_model/attribute_assignment.rb:48:in _assign_attribute': unknown attribute 'import_pass' for User. (ActiveModel::UnknownAttributeError) from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activemodel-5.1.4/lib/active_model/attribute_assignment.rb:40:in block in _assign_attributes’
from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activemodel-5.1.4/lib/active_model/attribute_assignment.rb:39:in each' from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activemodel-5.1.4/lib/active_model/attribute_assignment.rb:39:in _assign_attributes’
from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activerecord-5.1.4/lib/active_record/attribute_assignment.rb:26:in _assign_attributes' from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activemodel-5.1.4/lib/active_model/attribute_assignment.rb:33:in assign_attributes’
from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activerecord-5.1.4/lib/active_record/core.rb:337:in initialize' from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activerecord-5.1.4/lib/active_record/inheritance.rb:66:in new’
from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/activerecord-5.1.4/lib/active_record/inheritance.rb:66:in new' from /home/localadmin/git/discourse/script/import_scripts/base.rb:313:in create_user’
from /home/localadmin/git/discourse/script/import_scripts/base.rb:242:in block in create_users' from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rack-mini-profiler-0.10.7/lib/patches/db/mysql2.rb:6:in each’
from /home/localadmin/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rack-mini-profiler-0.10.7/lib/patches/db/mysql2.rb:6:in each' from /home/localadmin/git/discourse/script/import_scripts/base.rb:230:in create_users’
from script/import_scripts/discuz_x.rb:163:in block in import_users' from /home/localadmin/git/discourse/script/import_scripts/base.rb:824:in block in batches’
from /home/localadmin/git/discourse/script/import_scripts/base.rb:823:in loop' from /home/localadmin/git/discourse/script/import_scripts/base.rb:823:in batches’
from script/import_scripts/discuz_x.rb:137:in import_users' from script/import_scripts/discuz_x.rb:56:in execute’
from /home/localadmin/git/discourse/script/import_scripts/base.rb:46:in perform' from script/import_scripts/discuz_x.rb:1064:in ’

It seems that the custom field “import_pass” are failed to handle somewhere.
Does this happen because some plugins are absent with my environment?