diff --git a/mozilla/gfx/src/Makefile.in b/mozilla/gfx/src/Makefile.in
index 031221ead54..6d74b5af06a 100644
--- a/mozilla/gfx/src/Makefile.in
+++ b/mozilla/gfx/src/Makefile.in
@@ -94,13 +94,18 @@ CPPSRCS = \
         nsNameValuePairDB.cpp \
         nsRenderingContextImpl.cpp \
         nsRect.cpp \
-        nsTransform2D.cpp \
         nsScriptableRegion.cpp \
         nsGraphicsImpl.cpp \
         nsPrintOptionsImpl.cpp \
         nsPrintSettingsImpl.cpp \
         $(NULL)
 
+ifeq ($(OS_ARCH),OS2)
+CPPSRCS += nsTransform2DOS2.cpp
+else
+CPPSRCS += nsTransform2D.cpp
+endif
+
 ifeq (,$(filter windows,$(MOZ_WIDGET_TOOLKIT)))
 CPPSRCS += nsCompressedCharMap.cpp
 endif