prepare rc4

configure.ac

 AC_INIT([Gajim - A Jabber Instant Messager],
-		[0.12.5.90-rc1],[http://trac.gajim.org/],[gajim])
+		[0.12.5.90-rc4],[http://trac.gajim.org/],[gajim])
 AC_PREREQ([2.59])
 
 AC_CONFIG_HEADER(config.h)

src/common/defs.py

@@ -27,7 +27,7 @@ docdir = '../'
 datadir = '../'
 localedir = '../po'
 
-version = '0.12.5.90-rc1'
+version = '0.12.5.90-rc4'
 
 import sys, os.path
 for base in ('.', 'common'):