diff --git a/sc2/ChangeLog b/sc2/ChangeLog
index 26fb99b14..46b89e9af 100644
--- a/sc2/ChangeLog
+++ b/sc2/ChangeLog
@@ -1,4 +1,5 @@
 Changes towards version 0.4:
+- The unix build script is now able to detect SDL on Darwin (bug #358) - SvdB
 - Resource units given more obviously when ordering a probe to
   self-destruct (bug #586), from Nic.
 - Shipyard "Combat Energy" changed to reflect the recharge rate (bug #522).
diff --git a/sc2/build/unix/build.docs b/sc2/build/unix/build.docs
index 0e181f8c2..51a0739f3 100644
--- a/sc2/build/unix/build.docs
+++ b/sc2/build/unix/build.docs
@@ -124,6 +124,9 @@ Information about programs used should be supplied in the following form:
     A command to be executed which should return 0 if the program is present
     on the system, or 1 otherwise. If not supplied, 'type' is
     used to check for the program in the path.
+    This command may include a shell command that modifies any of the
+    variables PROG_${PROGRAM}_FILE, PROG_${PROGRAM}_ACTION, or
+    PROG_${PROGRAM}_VERSION.
   - PROG_${PROGRAM}_VERSION (optional)
     A string that evaluates to the version of the executable that is
     present, if it is present.
@@ -150,10 +153,13 @@ Information about libraries used should be supplied in the following form:
     on the system, or 1 otherwise. If not supplied, an attempt is
     made to compile and link an empty C program with the flags as in
     LIB_${LIB}_CFLAGS and LIB_${LIB}_LDFLAGS.
+    This command may include a shell command that modifies any of the
+    variables PROG_${LIB}_FILE, PROG_${LIB}_ACTION, or
+    PROG_${LIB}_VERSION.
   - LIB_${LIB}_VERSION (optional)
     A string that evaluates to the version of the library that is
     present, if it is present.
-  - LIB_${PROGRAM}_PRESENT (set by the configuration program)
+  - LIB_${LIB}_PRESENT (set by the configuration program)
     0 if the library has been verified to be present
     1 if the library has been verified to be not present
     <empty> if the library hasn't been verified to be present
diff --git a/sc2/build/unix/config_functions b/sc2/build/unix/config_functions
index aab3b6f00..cebf273a4 100644
--- a/sc2/build/unix/config_functions
+++ b/sc2/build/unix/config_functions
@@ -107,14 +107,27 @@ lexlt() {
 # Description: check if a program is present in the path
 # Arguments:   
 have_program() {
-	local TEMP_NAME TEMP_FILE TEMP_VERSION
+	local PROG TEMP_NAME TEMP_FILE TEMP_VERSION TEMP_DETECT
 
-	eval eval TEMP_NAME="\\\"\$PROG_${1}_NAME\\\""
+	PROG="$1"
+	eval eval TEMP_NAME="\\\"\$PROG_${PROG}_NAME\\\""
 	if [ -z "$TEMP_NAME" ]; then
-		echo "Fatal: Program '$1' is not defined!" >&2
+		echo "Fatal: Program '$PROG' is not defined!" >&2
 		exit 1
 	fi
-	eval eval TEMP_FILE="\\\"\$PROG_${1}_FILE\\\""
+	
+	eval eval TEMP_DETECT="\\\"\$PROG_${PROG}_DETECT\\\""
+	if [ -n "$TEMP_DETECT" ]; then
+		$TEMP_DETECT
+		# NB. TEMP_DETECT should make sure PROG_${PROG}_VERSION and
+                # PROG_${PROG}_FILE are set.
+		if [ $? -ne 0 ]; then
+			build_message "$TEMP_NAME not found."
+			return 1
+		fi
+	fi
+
+	eval eval TEMP_FILE="\\\"\$PROG_${PROG}_FILE\\\""
 
 	type "$TEMP_FILE" 2>&1 > /dev/null
 	if [ $? -ne 0 ]; then
@@ -124,7 +137,7 @@ have_program() {
 
 	if [ $# -gt 1 ]; then
 		# Minimum version supplied
-		eval eval TEMP_VERSION="\\\"\$PROG_${1}_VERSION\\\""
+		eval eval TEMP_VERSION="\\\"\$PROG_${PROG}_VERSION\\\""
 		if [ -z "$TEMP_VERSION" ]; then
 			echo "Fatal: Could not determine version of $TEMP_NAME" >&2
 			exit 1
@@ -152,7 +165,7 @@ but version $2 is required!"
 #              1 - if the library is not found
 have_library() {
 	local LIB TEMP_NAME TEMP_PRESENT TEMP_LDFLAGS TEMP_CFLAGS \
-			TEMP_VERSION
+			TEMP_VERSION TEMP_DETECT
 
 	LIB="$1"
 	eval eval TEMP_NAME="\\\"\$LIB_${1}_NAME\\\""
@@ -165,23 +178,31 @@ have_library() {
 	if [ -n "$TEMP_PRESENT" ]; then
 		return "$TEMP_PRESENT"
 	fi
+	
+	eval eval TEMP_DETECT="\\\"\$LIB_${LIB}_DETECT\\\""
+	if [ -n "$TEMP_DETECT" ]; then
+		$TEMP_DETECT
+		# NB. TEMP_DETECT should make sure PROG_$LIB_VERSION is set.
+		# return value of $TEMP_DETECT is used below.
+	else
+		eval eval TEMP_LDFLAGS="\\\"\$LIB_${LIB}_LDFLAGS\\\""
+		eval eval TEMP_CFLAGS="\\\"\$LIB_${LIB}_CFLAGS\\\""
 
-	eval eval TEMP_LDFLAGS="\\\"\$LIB_${LIB}_LDFLAGS\\\""
-	eval eval TEMP_CFLAGS="\\\"\$LIB_${LIB}_CFLAGS\\\""
-
-	try_compile_c "$TEMP_CFLAGS" "$TEMP_LDFLAGS" << EOF
+		try_compile_c "$TEMP_CFLAGS" "$TEMP_LDFLAGS" << EOF
 int main(int argc, char *argv[]) {
 	(void) argc;  /* Get rid of unused variable warning */
 	(void) argv;  /* Get rid of unused variable warning */
 	return 0;
 }
 EOF
+	fi  # TEMP_DETECT not defined
+	
 	if [ $? -ne 0 ]; then
 		eval "LIB_${LIB}_PRESENT"=1
 		build_message "$TEMP_NAME not found."
 		return 1
 	fi
-	
+
 	if [ $# -gt 1 ]; then
 		# Minimum version supplied
 		eval eval TEMP_VERSION="\\\"\$LIB_${LIB}_VERSION\\\""
diff --git a/sc2/build/unix/config_proginfo b/sc2/build/unix/config_proginfo
index 92ac22788..5b1286e7c 100644
--- a/sc2/build/unix/config_proginfo
+++ b/sc2/build/unix/config_proginfo
@@ -76,6 +76,24 @@ case "$OSNAME" in
 	FreeBSD)  LIB_SDL_VERSION='$(sdl11-config --version)' ;;
 	*)        LIB_SDL_VERSION='$(sdl-config --version)' ;;
 esac
+case "$OSNAME" in
+	Darwin)
+		LIB_SDL_DETECT="Darwin_SDL_detect"
+		Darwin_SDL_detect() {
+			eval TEMP_LDFLAGS="\"$LIB_SDL_LDFLAGS\""
+			eval TEMP_CFLAGS="\"$LIB_SDL_CFLAGS\""
+			try_compile_c "$TEMP_CFLAGS" "$TEMP_LDFLAGS" << EOF
+#include "SDL.h"
+int main(int argc, char *argv[]) {
+	(void) argc;  /* Get rid of unused variable warning */
+	(void) argv;  /* Get rid of unused variable warning */
+	return 0;
+}
+EOF
+			return $?
+		}
+		;;
+esac
 
 LIB_SDL_mixer_NAME="SDL_mixer"
 LIB_SDL_mixer_CFLAGS="$LIB_SDL_CFLAGS"