diff --git a/package/ngircd/ngircd.mk b/package/ngircd/ngircd.mk
index d60ac06b8..13313a7f7 100644
--- a/package/ngircd/ngircd.mk
+++ b/package/ngircd/ngircd.mk
@@ -5,6 +5,7 @@
 ################################################################################
 
 NGIRCD_VERSION = 20.3
+NGIRCD_SOURCE = ngircd-$(NGIRCD_VERSION).tar.xz
 NGIRCD_SITE = ftp://ftp.berlios.de/pub/ngircd/
 NGIRCD_DEPENDENCIES = zlib
 NGIRCD_LICENSE = GPLv2+
diff --git a/package/radvd/radvd.mk b/package/radvd/radvd.mk
index 27ce7e772..22ab9f9b3 100644
--- a/package/radvd/radvd.mk
+++ b/package/radvd/radvd.mk
@@ -5,6 +5,7 @@
 ################################################################################
 
 RADVD_VERSION = 1.9.7
+RADVD_SOURCE = radvd-$(RADVD_VERSION).tar.xz
 RADVD_SITE = http://www.litech.org/radvd/dist
 RADVD_DEPENDENCIES = host-bison flex libdaemon host-flex host-pkgconf
 
diff --git a/package/tar/tar.mk b/package/tar/tar.mk
index f748724be..369dc9d52 100644
--- a/package/tar/tar.mk
+++ b/package/tar/tar.mk
@@ -5,6 +5,7 @@
 ################################################################################
 
 TAR_VERSION = 1.27.1
+TAR_SOURCE = tar-$(TAR_VERSION).tar.xz
 TAR_SITE = $(BR2_GNU_MIRROR)/tar
 TAR_LICENSE = GPLv3+
 TAR_LICENSE_FILES = COPYING