diff --git a/core/c/jbigi/mbuild-all.sh b/core/c/jbigi/mbuild-all.sh
index 3740af26d626d3ffffea7b98dd8a1bb8abe81916..5ec7d087310a1e8956f037223b490bff0769a877 100755
--- a/core/c/jbigi/mbuild-all.sh
+++ b/core/c/jbigi/mbuild-all.sh
@@ -114,7 +114,7 @@ NetBSD*|FreeBSD*|OpenBSD*)
 	NAME="libjbigi"
 	TYPE="so"
 	PLATFORM_LIST=""
-	BSDTYPE="`uname -s | tr [A-Z] [a-z]`"
+	BSDTYPE=$(uname -s | tr "[A-Z]" "[a-z]")
 	arch=$(uname -m | cut -f1 -d" ")
 	case ${arch} in
 		i[3-6]86)
diff --git a/core/c/jbigi/mbuild_jbigi.sh b/core/c/jbigi/mbuild_jbigi.sh
index 4b505d1e16b1682400532df46d302ff65ef5945c..855260f99cc553a1ef6b9933218d84a68d5b1064 100755
--- a/core/c/jbigi/mbuild_jbigi.sh
+++ b/core/c/jbigi/mbuild_jbigi.sh
@@ -24,7 +24,7 @@ Darwin*)
         LINKFLAGS="-dynamiclib -framework JavaVM"
         LIBFILE="libjbigi.jnilib";;
 SunOS*|OpenBSD*|NetBSD*|FreeBSD*|Linux*)
-        UNIXTYPE="`uname -s | tr [A-Z] [a-z]`"
+        UNIXTYPE=$(uname -s | tr "[A-Z]" "[a-z]")
         if [ $UNIXTYPE = "sunos" ]; then
                 UNIXTYPE="solaris"
         elif [ $UNIXTYPE = "freebsd" ]; then