gistfile1.rb

#!/usr/bin/env ruby

# We use the actual id's here
dod_id = IssueCustomField.find_by_name('Akzeptanzkriterien').id
timespan_id = IssueCustomField.find_by_name('Zeitaufwand').id
precond_id = IssueCustomField.find_by_name('Vorbedingungen').id
lane_id = IssueCustomField.find_by_name('Lane').id

rows.each do |row|

[...]

  issue = Issue.build :subject => subject, :description => user_story, :project => project , :tracker => tracker, :author => author
  issue.custom_field_values = {
    dod_id.to_s => dod,
    timespan_id => 'M',
    precond_id => 'keine',
    lane_id => 'Product Owner'
  }
  issue.save!
end