diff --git a/make/tex.mk b/make/tex.mk
index ed6ea538..9bfdfbe7 100644
--- a/make/tex.mk
+++ b/make/tex.mk
@@ -106,20 +106,20 @@ define mangle_tmpl
 		s%__ICON_NEXT__%$(ICON_NEXT)%g; \
 		s%__DOCUMENT_CLASS__%$(DOCUMENT_CLASS)%g; \
 		s%__UPLOAD_SERVER_PATH__%$(UPLOAD_SERVER_PATH)%g; \
-		s%ä%\"a%g; \
-		s%Ä%\"A%g; \
-		s%ö%\"o%g; \
-		s%Ö%\"O%g; \
-		s%ü%\"u%g; \
-		s%Ü%\"U%g; \
-		s%ß%\"s%g; \
-		s%\xc3\xa4%\"a%g; \
-		s%\xc3\x84%\"A%g; \
-		s%\xc3\xb6%\"o%g; \
-		s%\xc3\x96%\"O%g; \
-		s%\xc3\xbc%\"u%g; \
-		s%\xc3\x9c%\"U%g; \
-		s%\xc3\x9f%\"s%g; \
+		s%ä%\\\\\"a%g; \
+		s%Ä%\\\\\"A%g; \
+		s%ö%\\\\\"o%g; \
+		s%Ö%\\\\\"O%g; \
+		s%ü%\\\\\"u%g; \
+		s%Ü%\\\\\"U%g; \
+		s%ß%\\\"s%g; \
+		s%\xc3\xa4%\\\\\"a%g; \
+		s%\xc3\x84%\\\\\"A%g; \
+		s%\xc3\xb6%\\\\\"o%g; \
+		s%\xc3\x96%\\\\\"O%g; \
+		s%\xc3\xbc%\\\\\"u%g; \
+		s%\xc3\x9c%\\\\\"U%g; \
+		s%\xc3\x9f%\\\"s%g; \
 	" | awk '                                              \
 		BEGIN { FS=":" } {                             \
 		if ($$0 ~ /SUBST_LINE_NUM/) {                  \