Redmine

Stating in this thread; http://www.redmine.org/boards/1/topics/36091?r=36121 this is now be something to say "Help me please".

If I try to access an ticket or something else of a project I get this error:

Started GET "/projects/rss-to-me/issues" for 79.197.136.150 at Wed Feb 06 21:55:11 +0100 2013
Processing by IssuesController#index as HTML
Parameters: {"project_id"=>"rss-to-me"}
Current user: sebastian (id=1)
Rendered queries/_filters.html.erb (29.9ms)
Rendered queries/_columns.html.erb (5.6ms)
Rendered issues/_list.html.erb (16.0ms)
Rendered issues/index.html.erb within layouts/base (61.5ms)
Completed 500 Internal Server Error in 151ms

ActionView::Template::Error (undefined local variable or method `position_name' for #<IssuePriority:0x2ac9f98f0c80>):
29: </td>
30: </tr>
31: <% previous_group = group >
32: < end >
33: <tr id="issue-<= issue.id >" class="hascontextmenu <= cycle('odd', 'even') > <= issue.css_classes > <= level > 0 ? "idnt idnt-#{level}" : nil >">
34: <td class="checkbox hide-when-print"><= check_box_tag("ids[]", issue.id, false, :id => nil) ></td>
35: <td class="id"><= link_to issue.id, issue_path(issue) %></td>
app/models/issue_priority.rb:39:in `css_classes'
app/models/issue.rb:939:in `css_classes'
app/views/issues/_list.html.erb:32:in `_app_views_issues__list_html_erb__1651667054_23523484668240'
app/helpers/issues_helper.rb:29:in `issue_list'
app/helpers/issues_helper.rb:25:in `each'
app/helpers/issues_helper.rb:25:in `issue_list'
app/views/issues/_list.html.erb:19:in `_app_views_issues__list_html_erb__1651667054_23523484668240'
app/views/issues/_list.html.erb:1:in `_app_views_issues__list_html_erb__1651667054_23523484668240'
app/views/issues/index.html.erb:62:in `_app_views_issues_index_html_erb__841582362_23523482057280'
app/controllers/issues_controller.rb:83
app/controllers/issues_controller.rb:82:in `index'

what can I do? I recently updated my redmine form 2.1.4 to 2.2.2 - in other part I don't know why he use ruby 1.8.7 instead of 1.9.x that is installed too.