Using searchlogic with acts_as_taggable_on

Hi,

i have 2 model, Merchant and Items and using acts_as_taggable_on
Merchant has_many Items, and i try to find Merchant with search logic
including the tags

class Merchant < ActiveRecord::Base
  acts_as_taggable

  has_many :items
end

class Item < ActiveRecord::Base
  acts_as_taggable

  belongs_to :merchant
end

This works

Merchant.tagged_with('Tag 1')

but this doesn't

Merchant.tagged_with_or_name_like('Tag 1')

Searchlogic::NamedScopes::OrConditions::UnknownConditionError: The
condition 'tagged_with' is not a valid condition, we could not find
any scopes that match this.

Can anybody help me with this ?

Thanks