diff --git a/rhodecode/lib/vcs/backends/base.py b/rhodecode/lib/vcs/backends/base.py
--- a/rhodecode/lib/vcs/backends/base.py
+++ b/rhodecode/lib/vcs/backends/base.py
@@ -485,9 +485,9 @@ class BaseRepository(object):
         :param close_branch: If `True` branch will be close before merging it
         """
         if dry_run:
-            message = message or 'dry_run_merge_message'
-            user_email = user_email or 'dry-run-merge@rhodecode.com'
-            user_name = user_name or 'Dry-Run User'
+            message = message or settings.MERGE_DRY_RUN_MESSAGE
+            user_email = user_email or settings.MERGE_DRY_RUN_EMAIL
+            user_name = user_name or settings.MERGE_DRY_RUN_USER
         else:
             if not user_name:
                 raise ValueError('user_name cannot be empty')
diff --git a/rhodecode/lib/vcs/conf/settings.py b/rhodecode/lib/vcs/conf/settings.py
--- a/rhodecode/lib/vcs/conf/settings.py
+++ b/rhodecode/lib/vcs/conf/settings.py
@@ -54,6 +54,14 @@ HOOKS_DIRECT_CALLS = False
 HOOKS_HOST = '127.0.0.1'
 
 
+MERGE_MESSAGE_TMPL = (
+    u'Merge pull request #{pr_id} from {source_repo} {source_ref_name}\n\n '
+    u'{pr_title}')
+MERGE_DRY_RUN_MESSAGE = 'dry_run_merge_message_from_rhodecode'
+MERGE_DRY_RUN_USER = 'Dry-Run User'
+MERGE_DRY_RUN_EMAIL = 'dry-run-merge@rhodecode.com'
+
+
 def available_aliases():
     """
     Mercurial is required for the system to work, so in case vcs.backends does
diff --git a/rhodecode/model/pull_request.py b/rhodecode/model/pull_request.py
--- a/rhodecode/model/pull_request.py
+++ b/rhodecode/model/pull_request.py
@@ -608,23 +608,24 @@ class PullRequestModel(BaseModel):
     def _merge_pull_request(self, pull_request, user, extras, merge_msg=None):
         target_vcs = pull_request.target_repo.scm_instance()
         source_vcs = pull_request.source_repo.scm_instance()
-        target_ref = self._refresh_reference(
-            pull_request.target_ref_parts, target_vcs)
 
-        message = merge_msg or (
-            'Merge pull request #%(pr_id)s from '
-            '%(source_repo)s %(source_ref_name)s\n\n %(pr_title)s') % {
-                'pr_id': pull_request.pull_request_id,
-                'source_repo': source_vcs.name,
-                'source_ref_name': pull_request.source_ref_parts.name,
-                'pr_title': pull_request.title
-            }
+        message = safe_unicode(merge_msg or vcs_settings.MERGE_MESSAGE_TMPL).format(
+            pr_id=pull_request.pull_request_id,
+            pr_title=pull_request.title,
+            source_repo=source_vcs.name,
+            source_ref_name=pull_request.source_ref_parts.name,
+            target_repo=target_vcs.name,
+            target_ref_name=pull_request.target_ref_parts.name,
+        )
 
         workspace_id = self._workspace_id(pull_request)
         repo_id = pull_request.target_repo.repo_id
         use_rebase = self._use_rebase_for_merging(pull_request)
         close_branch = self._close_branch_before_merging(pull_request)
 
+        target_ref = self._refresh_reference(
+            pull_request.target_ref_parts, target_vcs)
+
         callback_daemon, extras = prepare_callback_daemon(
             extras, protocol=vcs_settings.HOOKS_PROTOCOL,
             host=vcs_settings.HOOKS_HOST,
@@ -635,10 +636,12 @@ class PullRequestModel(BaseModel):
             # for a single call.
             target_vcs.config.set(
                 'rhodecode', 'RC_SCM_DATA', json.dumps(extras))
+
+            user_name = user.short_contact
             merge_state = target_vcs.merge(
                 repo_id, workspace_id, target_ref, source_vcs,
                 pull_request.source_ref_parts,
-                user_name=user.username, user_email=user.email,
+                user_name=user_name, user_email=user.email,
                 message=message, use_rebase=use_rebase,
                 close_branch=close_branch)
         return merge_state
diff --git a/rhodecode/tests/models/test_pullrequest.py b/rhodecode/tests/models/test_pullrequest.py
--- a/rhodecode/tests/models/test_pullrequest.py
+++ b/rhodecode/tests/models/test_pullrequest.py
@@ -305,7 +305,7 @@ class TestPullRequestModel(object):
             pull_request.target_ref_parts,
             pull_request.source_repo.scm_instance(),
             pull_request.source_ref_parts,
-            user_name=user.username, user_email=user.email, message=message,
+            user_name=user.short_contact, user_email=user.email, message=message,
             use_rebase=False, close_branch=False
         )
         self.invalidation_mock.assert_called_once_with(
@@ -345,7 +345,7 @@ class TestPullRequestModel(object):
             pull_request.target_ref_parts,
             pull_request.source_repo.scm_instance(),
             pull_request.source_ref_parts,
-            user_name=user.username, user_email=user.email, message=message,
+            user_name=user.short_contact, user_email=user.email, message=message,
             use_rebase=False, close_branch=False
         )