diff --git a/externals/Makefile.am b/externals/Makefile.am
index 981506ebb0..722994c9aa 100644
--- a/externals/Makefile.am
+++ b/externals/Makefile.am
@@ -75,12 +75,12 @@ endif
 
 # bzip2
 
-BZIP2 = bzip2-1.0.4
+BZIP2 = bzip2-1.0.5
 
 $(BZIP2).tar.gz:
 	@echo "Nix requires bzip2 to build."
-	@echo "Please download version 1.0.4 from"
-	@echo "  http://www.bzip.org/1.0.4/bzip2-1.0.4.tar.gz"
+	@echo "Please download version 1.0.5 from"
+	@echo "  http://www.bzip.org/1.0.5/bzip2-1.0.5.tar.gz"
 	@echo "and place it in the externals/ directory."
 	false