diff --git a/configure.ac b/configure.ac
index a8d896008ecb38e99b93b0fa6504a14cad1480b3..a6aadddfc56aff15e7f74cd2772ed23519e033bf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,5 +1,5 @@
 AC_INIT([Gajim - A Jabber Instant Messager],
-		[0.12.5.5-dev],[http://trac.gajim.org/],[gajim])
+		[0.12.5.6-dev],[http://trac.gajim.org/],[gajim])
 AC_PREREQ([2.59])
 
 AC_CONFIG_HEADER(config.h)
diff --git a/src/common/defs.py b/src/common/defs.py
index 1b4ba22d589bb6502fcee9e30660b8355157cff2..92bcb527c68d7b69fa00060cd60b97df93f98699 100644
--- a/src/common/defs.py
+++ b/src/common/defs.py
@@ -27,7 +27,7 @@ docdir = '../'
 datadir = '../'
 localedir = '../po'
 
-version = '0.12.5.5-dev'
+version = '0.12.5.6-dev'
 
 import sys, os.path
 for base in ('.', 'common'):
diff --git a/src/common/optparser.py b/src/common/optparser.py
index 62d69d377c43ff0f850eb9316c8e8bde05fb941f..05821a2e07c22513e678d6ca5c8f6741d09a96d3 100644
--- a/src/common/optparser.py
+++ b/src/common/optparser.py
@@ -210,6 +210,8 @@ class OptionsParser:
 			self.update_config_to_01254()
 		if old < [0, 12, 5, 5] and new >= [0, 12, 5, 5]:
 			self.update_config_to_01255()
+		if old < [0, 12, 5, 6] and new >= [0, 12, 5, 6]:
+			self.update_config_to_01256()
 
 		gajim.logger.init_vars()
 		gajim.config.set('version', new_version)
@@ -780,4 +782,15 @@ class OptionsParser:
 				gajim.config.set(c, vals[c][1])
 		gajim.config.set('version', '0.12.5.5')
 
+	def update_config_to_01256(self):
+		vals = {'gc_nicknames_colors': ['#4e9a06:#f57900:#ce5c00:#3465a4:#204a87:#75507b:#5c3566:#c17d11:#8f5902:#ef2929:#cc0000:#a40000', '#f57900:#ce5c00:#204a87:#75507b:#5c3566:#c17d11:#8f5902:#ef2929:#cc0000:#a40000']}
+		for c in vals:
+			if c not in self.old_values:
+				continue
+			val = self.old_values[c]
+			if val == vals[c][0]:
+				# We didn't change default value, so update it with new default
+				gajim.config.set(c, vals[c][1])
+		gajim.config.set('version', '0.12.5.6')
+
 # vim: se ts=3: