diff --git a/app/helpers/issues_helper.rb b/app/helpers/issues_helper.rb
index 0d1301d0..3f802727 100644
--- a/app/helpers/issues_helper.rb
+++ b/app/helpers/issues_helper.rb
@@ -42,15 +42,21 @@ module IssuesHelper
   end
 
   def url_for_issue(issue_id)
+    return "" if @project.nil?
+
     if @project.used_default_issues_tracker?
       url = project_issue_url project_id: @project, id: issue_id
     else
       url = Settings[:issues_tracker][@project.issues_tracker]["issues_url"]
-      url.gsub(':id', issue_id.to_s).gsub(':project_id', @project.id.to_s)
+      url.gsub(':id', issue_id.to_s)
+        .gsub(':project_id', @project.id.to_s)
+        .gsub(':issues_tracker_id', @project.issues_tracker_id.to_s)
     end
   end
 
   def title_for_issue(issue_id)
+    return "" if @project.nil?
+
     if @project.used_default_issues_tracker? && issue = @project.issues.where(id: issue_id).first
       issue.title
     else
diff --git a/spec/helpers/issues_helper_spec.rb b/spec/helpers/issues_helper_spec.rb
new file mode 100644
index 00000000..7d2ac8c7
--- /dev/null
+++ b/spec/helpers/issues_helper_spec.rb
@@ -0,0 +1,54 @@
+require "spec_helper"
+
+describe IssuesHelper do
+  let(:project) { create(:project) }
+  let(:issue) { create(:issue, project: project) }
+  let(:ext_project) { create(:redmine_project) }
+
+  describe :title_for_issue do
+    it "should return issue title if used internal tracker" do
+      @project = project
+      title_for_issue(issue.id).should eq issue.title
+    end
+
+    it "should always return empty string if used external tracker" do
+      @project = ext_project
+      title_for_issue(rand(100)).should eq ""
+    end
+
+    it "should always return empty string if project nil" do
+      @project = nil
+
+      title_for_issue(rand(100)).should eq ""
+    end
+  end
+
+  describe :url_for_issue do
+    let(:issue_id) { 3 }
+    let(:issues_url) { "http://redmine/:project_id/:issues_tracker_id/:id" }
+    let(:ext_expected) do
+      issues_url.gsub(':id', issue_id.to_s)
+        .gsub(':project_id', ext_project.id.to_s)
+        .gsub(':issues_tracker_id', ext_project.issues_tracker_id.to_s)
+    end
+    let(:int_expected) { polymorphic_path([project, issue]) }
+
+    it "should return internal path if used internal tracker" do
+      @project = project
+      url_for_issue(issue.id).should match(int_expected)
+    end
+
+    it "should return path to external tracker" do
+      @project = ext_project
+      Settings[:issues_tracker][ext_project.issues_tracker]["issues_url"] = issues_url
+
+      url_for_issue(issue_id).should match(ext_expected)
+    end
+
+    it "should return empty string if project nil" do
+      @project = nil
+
+      url_for_issue(issue.id).should eq ""
+    end
+  end
+end