diff --git a/src/getchar.c b/src/getchar.c
index cc30f94..7455c77 100644
--- a/src/getchar.c
+++ b/src/getchar.c
@@ -2206,10 +2206,16 @@
 #ifdef FEAT_MBYTE
 				/* Don't allow mapping the first byte(s) of a
 				 * multi-byte char.  Happens when mapping
-				 * <M-a> and then changing 'encoding'. */
-				if (has_mbyte && MB_BYTE2LEN(c1)
-						  > (*mb_ptr2len)(mp->m_keys))
-				    mlen = 0;
+				 * <M-a> and then changing 'encoding'. Beware
+				 * that 0x80 is escaped. */
+				{
+				    char_u *p1 = mp->m_keys;
+				    char_u *p2 = mb_unescape(&p1);
+
+				    if (has_mbyte && p2 != NULL
+					  && MB_BYTE2LEN(c1) > MB_PTR2LEN(p2))
+					mlen = 0;
+				}
 #endif
 				/*
 				 * Check an entry whether it matches.
diff --git a/src/testdir/test75.in b/src/testdir/test75.in
index 4bd8279..b7f2783 100644
--- a/src/testdir/test75.in
+++ b/src/testdir/test75.in
@@ -1,8 +1,11 @@
 Tests for maparg().
+Also test utf8 map with a 0x80 byte.
 
 STARTTEST
 :so small.vim
+:so mbyte.vim
 :set cpo-=<
+:set encoding=utf8
 :" Test maparg() with a string result
 :map foo<C-V> is<F4>foo
 :vnoremap <script> <buffer> <expr> <silent> bar isbar
@@ -17,6 +20,20 @@
 :map abc y<S-char-114>y
 :call append('$', maparg('abc'))
 :"
+Go:"
+:" Outside of the range, minimum
+:inoremap <Char-0x1040> a
+:call feedkeys("a\u1040\<Esc>")
+:" Inside of the range, minimum
+:inoremap <Char-0x103f> b
+:call feedkeys("a\u103f\<Esc>")
+:" Inside of the range, maximum
+:inoremap <Char-0xf03f> c
+:call feedkeys("a\uf03f\<Esc>")
+:" Outside of the range, maximum
+:inoremap <Char-0xf040> d
+:call feedkeys("a\uf040\<Esc>")
+:"
 :/^eof/+1,$w! test.out
 :qa!
 ENDTEST
diff --git a/src/testdir/test75.ok b/src/testdir/test75.ok
index d8f9a2a..a2c5c5a 100644
--- a/src/testdir/test75.ok
+++ b/src/testdir/test75.ok
@@ -4,3 +4,4 @@
 {'silent': 0, 'noremap': 0, 'lhs': 'foo', 'mode': ' ', 'nowait': 1, 'expr': 0, 'sid': 0, 'rhs': 'bar', 'buffer': 1}
 xrx
 yRy
+abcd
diff --git a/src/version.c b/src/version.c
index 112e168..5a50c2e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    204,
+/**/
     203,
 /**/
     202,