diff --git a/api/texfont.cpp b/api/texfont.cpp
index 9c059b5a98..fdf2019576 100644
--- a/api/texfont.cpp
+++ b/api/texfont.cpp
@@ -518,6 +518,9 @@ void txfRenderGlyph(TexFont * txf, int c){
 void txfRenderString(TexFont * txf, char *string, int len){
 	int i;
 	for (i = 0; i < len; i++) {
+        if (!isascii(string[i])) {
+            string[i] = '?';
+        }
 		txfRenderGlyph(txf, string[i]);
 	}
 }
diff --git a/checkin_notes b/checkin_notes
index e61dc4f891..0d5df3c704 100644
--- a/checkin_notes
+++ b/checkin_notes
@@ -1313,3 +1313,10 @@ David  18 Feb 2010
     lib/
         app_ipc.cpp
         gui_rpc_client_ops.cpp
+
+David  18 Feb 2010
+	- API: in txfRenderString, replace non-ASCII chars with ?.
+		Otherwise it calls abort()!
+
+	api/
+		texfont.cpp