diff --git a/src/utility/zstrformat.cpp b/src/utility/zstrformat.cpp
index 2bec17803..bf61ce282 100644
--- a/src/utility/zstrformat.cpp
+++ b/src/utility/zstrformat.cpp
@@ -89,6 +89,7 @@
 
 #include "zstring.h"
 #include "gdtoa.h"
+#include "utf8.h"
 
 
 /*
@@ -557,8 +558,11 @@ namespace StringFormat
 		else if (type == 'c')
 		{
 			intarg = va_arg (arglist, int);
-			buffer[0] = char(intarg);
-			bufflen = 1;
+			if (utf8_encode(intarg, (uint8_t*)buffer, &bufflen) != 0)
+			{
+				buffer[0] = '?';
+				bufflen = 1;
+			}
 			obuff = buffer;
 		}
 		else if (type == 's')
diff --git a/wadsrc/static/zscript/menu/textentermenu.txt b/wadsrc/static/zscript/menu/textentermenu.txt
index a7cbdb517..328c7aa94 100644
--- a/wadsrc/static/zscript/menu/textentermenu.txt
+++ b/wadsrc/static/zscript/menu/textentermenu.txt
@@ -209,9 +209,7 @@ class TextEnterMenu : Menu
 
 	private void AppendChar(int ch)
 	{
-		String newstring = mEnterString;
-		newstring.AppendCharacter(ch);
-		newstring = newstring .. displayFont.GetCursor();
+		String newstring = String.Format("%s%c%s", mEnterString, ch, displayFont.GetCursor());
 		if (mEnterSize < 0 || displayFont.StringWidth(newstring) < mEnterSize)
 		{
 			mEnterString.AppendCharacter(ch);