diff --git a/gitfixtures.py b/gitfixtures.py
index d201118..b87ca9f 100644
--- a/gitfixtures.py
+++ b/gitfixtures.py
@@ -37,7 +37,7 @@ class GitFixtures(Fixtures):
         tag = 'tag' + str(rev_num)
         self.run('tag ' + tag)
         self.revs[rev_num]   = tag
-        self.timestamps[tag] = self.get_metadata('%at')
+        self.timestamps[tag] = self.get_metadata('%ct')
         self.sha1s[tag]      = self.get_metadata('%h')
         self.scmlogs.annotate(
             "Recorded rev %d: id %s, timestamp %s, SHA1 %s" % \
diff --git a/gittests.py b/gittests.py
index 2471004..34db4d3 100644
--- a/gittests.py
+++ b/gittests.py
@@ -11,7 +11,7 @@ class GitTests(GitHgTests):
     fixtures_class = GitFixtures
 
     abbrev_hash_format = '%h'
-    timestamp_format   = '%at'
+    timestamp_format   = '%ct'
 
     def default_version(self):
         return self.timestamps(self.rev(2))
diff --git a/obs-service-tar_scm.changes b/obs-service-tar_scm.changes
index 4178de3..f75742f 100644
--- a/obs-service-tar_scm.changes
+++ b/obs-service-tar_scm.changes
@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Mon Oct  1 07:15:03 UTC 2012 - cthiel@suse.com
+
+- change default versionformat from author date (%at) to commiter date (%ct)
+  for git, to fix issues with cherry-picked commits resulting in decreased
+  version
+
 -------------------------------------------------------------------
 Mon Sep 24 11:47:27 UTC 2012 - jslaby@suse.com
 
diff --git a/tar_scm b/tar_scm
index 0c10665..99ef0f6 100644
--- a/tar_scm
+++ b/tar_scm
@@ -378,7 +378,7 @@ detect_version () {
   if [ -z "$MYFORMAT" ]; then
     case "$MYSCM" in
       git)
-        MYFORMAT="%at"
+        MYFORMAT="%ct"
         ;;
       hg)
         MYFORMAT="{rev}"
diff --git a/tar_scm.service b/tar_scm.service
index 35b7914..4db275b 100644
--- a/tar_scm.service
+++ b/tar_scm.service
@@ -20,7 +20,7 @@
     <description>Specify version to be used in tarball. Defaults to automatically detected value formatted by versionformat parameter.</description>
   </parameter>
   <parameter name="versionformat">
-    <description>Auto-generate version from checked out source using this format string. For git, value is passed via git show --pretty=format:... (default '%at'); for hg, via hg log --template=... (default '{rev}'); for bzr and svn, %r is revision (default '%r'). Overrides tarball name defined by version parameter.</description>
+    <description>Auto-generate version from checked out source using this format string. For git, value is passed via git show --pretty=format:... (default '%ct'); for hg, via hg log --template=... (default '{rev}'); for bzr and svn, %r is revision (default '%r'). Overrides tarball name defined by version parameter.</description>
   </parameter>
   <parameter name="versionprefix">
     <description>specify a base version as prefix.</description>