diff --git a/Makefile b/Makefile
index ee291a49..a6711957 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,12 @@
-VERSION=1.73.0
-SVNREVISION=`svn info  | grep Revision | cut -d ' ' -f 2`
-BUILDTIME=`date \"+%Y.%m.%d %H.%M\"`
+# Build version string, taking into account that 'VER_REV' may not be set
+VERSION     := $(shell cat src/Cocoa/oolite-version.xcconfig | cut -d '=' -f 2)
+VER_MAJ     := $(strip $(shell echo "${VERSION}" | cut -d '.' -f 1))
+VER_MIN     := $(strip $(shell echo "${VERSION}" | cut -d '.' -f 2))
+VER_REV     := $(strip $(shell echo "${VERSION}" | cut -d '.' -f 3))
+VER_REV     := $(if ${VER_REV},${VER_REV},0)
+SVNREVISION := $(shell svn info  | grep Revision | cut -d ' ' -f 2)
+VER         := $(shell echo "${VER_MAJ}.${VER_MIN}.${VER_REV}.${SVNREVISION}")
+BUILDTIME   := $(shell date "+%Y.%m.%d %H:%M")
 
 LIBJS_SRC_DIR=deps/Cross-platform-deps/SpiderMonkey/js/src
 
@@ -73,8 +79,11 @@ NSISVERSIONS=installers/win32/OoliteVersions.nsh
 ${NSISVERSIONS}:
 	@echo "; Version Definitions for Oolite" > $@
 	@echo "; NOTE - This file is auto-generated by the Makefile, any manual edits will be overwritten" >> $@
-	@echo "!define VERSION ${VERSION}" >> $@
+	@echo "!define VER_MAJ ${VER_MAJ}" >> $@
+	@echo "!define VER_MIN ${VER_MIN}" >> $@
+	@echo "!define VER_REV ${VER_REV}" >> $@
 	@echo "!define SVNREV ${SVNREVISION}" >> $@
+	@echo "!define VERSION ${VER}" >> $@
 	@echo "!define BUILDTIME \"${BUILDTIME}\"" >> $@
 
 .PHONY: pkg-win
diff --git a/installers/win32/OOlite.nsi b/installers/win32/OOlite.nsi
index bbc630de..bff13ee5 100644
--- a/installers/win32/OOlite.nsi
+++ b/installers/win32/OOlite.nsi
@@ -3,13 +3,16 @@
 !include /NONFATAL "OoliteVersions.nsh"
 
 !ifndef SVNREV
+!warning "No SVN Revision supplied"
 !define SVNREV 0
 !endif
-!ifndef VER
+!ifndef VERSION
+!warning "No Version information supplied"
+!define VERSION 0.0.0.0
+!endif
 ; Version number must be of format X.X.X.X.
 ; We use M.m.R.S:  M-major, m-minor, R-revision, S-subversion
-!define VER 1.73.0.${SVNREV}
-!endif
+!define VER ${VERSION}
 !ifndef DST
 !define DST ..\..\oolite.app
 !endif
@@ -20,7 +23,6 @@
 !ifndef SNAPSHOT
 !define EXTVER ""
 !else
-!define SVNREVSTR ".r${SVNREV}"
 !define EXTVER "-dev"
 !endif