diff --git a/configure b/configure
index 072c09ed2a..ee546e03c7 100755
--- a/configure
+++ b/configure
@@ -9207,25 +9207,25 @@ $as_echo "configuring" >&6; }
 
 		this_host=$(./config.sub $(./config.guess))
 		if test "$build" != "$this_host" ; then
-			PJPROJECT_CONFIGURE_OPTS+=" --build=$build_alias"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --build=$build_alias"
 		fi
 		if test "$host" != "$this_host" ; then
-			PJPROJECT_CONFIGURE_OPTS+=" --host=$host_alias"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --host=$host_alias"
 		fi
 		# This was a copy of the autoconf generated code from the root ./configure.
 		# Hopefully, when you read this, the code is still the same.
 		if test "${with_ssl+set}" = set; then :
 			case $with_ssl in
 			n|no)
-			PJPROJECT_CONFIGURE_OPTS+=" --disable-ssl"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --disable-ssl"
 			;;
 			y|ye|yes)
 			# Not to mention SSL is the default in PJProject and means "autodetect".
 			# In Asterisk, "./configure --with-ssl" means "must be present".
-			PJPROJECT_CONFIGURE_OPTS+=""
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS}"
 			;;
 			*)
-			PJPROJECT_CONFIGURE_OPTS+=" --with-ssl=${with_ssl}"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --with-ssl=${with_ssl}"
 			;;
 			esac
 		fi
diff --git a/third-party/pjproject/configure.m4 b/third-party/pjproject/configure.m4
index 7cbb30781f..485e4f1a74 100644
--- a/third-party/pjproject/configure.m4
+++ b/third-party/pjproject/configure.m4
@@ -51,25 +51,25 @@ AC_DEFUN([_PJPROJECT_CONFIGURE],
 		AC_ARG_VAR([PJPROJECT_CONFIGURE_OPTS],[Additional configure options to pass to bundled pjproject])
 		this_host=$(./config.sub $(./config.guess))
 		if test "$build" != "$this_host" ; then
-			PJPROJECT_CONFIGURE_OPTS+=" --build=$build_alias"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --build=$build_alias"
 		fi
 		if test "$host" != "$this_host" ; then
-			PJPROJECT_CONFIGURE_OPTS+=" --host=$host_alias"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --host=$host_alias"
 		fi
 		# This was a copy of the autoconf generated code from the root ./configure.
 		# Hopefully, when you read this, the code is still the same.
 		if test "${with_ssl+set}" = set; then :
 			case $with_ssl in
 			n|no)
-			PJPROJECT_CONFIGURE_OPTS+=" --disable-ssl"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --disable-ssl"
 			;;
 			y|ye|yes)
 			# Not to mention SSL is the default in PJProject and means "autodetect".
 			# In Asterisk, "./configure --with-ssl" means "must be present".
-			PJPROJECT_CONFIGURE_OPTS+=""
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS}"
 			;;
 			*)
-			PJPROJECT_CONFIGURE_OPTS+=" --with-ssl=${with_ssl}"
+			PJPROJECT_CONFIGURE_OPTS="${PJPROJECT_CONFIGURE_OPTS} --with-ssl=${with_ssl}"
 			;;
 			esac
 		fi