diff --git a/conf/intel/portage/package.mask/00-sabayon.package.mask b/conf/intel/portage/package.mask/00-sabayon.package.mask
index 589f12cf..c55a47bb 100644
--- a/conf/intel/portage/package.mask/00-sabayon.package.mask
+++ b/conf/intel/portage/package.mask/00-sabayon.package.mask
@@ -219,3 +219,6 @@ dev-libs/libgcrypt:11
 
 # 2016-08-23 Ettore Di Giacinto: use overlay version
 media-sound/mixxx::gentoo
+
+# 2016-08-26 Sławomir Nizio: net-misc/gns3-server (as of 1.5.1) depends on =dev-python/aiohttp-0.21.5
+>=dev-python/aiohttp-0.22.2