diff --git a/lauxlib.c b/lauxlib.c
index f2ba704..e6d7416 100644
--- a/lauxlib.c
+++ b/lauxlib.c
@@ -476,7 +476,7 @@
   UBox *box = (UBox *)lua_touserdata(L, idx);
   void *temp = allocf(ud, box->box, box->bsize, newsize);
   if (temp == NULL && newsize > 0)  /* allocation error? */
-    luaL_error(L, "not enough memory for buffer allocation");
+    luaL_error(L, "not enough memory");
   box->box = temp;
   box->bsize = newsize;
   return temp;
diff --git a/lutf8lib.c b/lutf8lib.c
index 3b36a60..901d985 100644
--- a/lutf8lib.c
+++ b/lutf8lib.c
@@ -97,9 +97,9 @@
   lua_Integer posj = u_posrelat(luaL_optinteger(L, 3, -1), len);
   int lax = lua_toboolean(L, 4);
   luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 2,
-                   "initial position out of string");
+                   "initial position out of bounds");
   luaL_argcheck(L, --posj < (lua_Integer)len, 3,
-                   "final position out of string");
+                   "final position out of bounds");
   while (posi <= posj) {
     const char *s1 = utf8_decode(s + posi, NULL, !lax);
     if (s1 == NULL) {  /* conversion error? */
@@ -127,8 +127,8 @@
   int lax = lua_toboolean(L, 4);
   int n;
   const char *se;
-  luaL_argcheck(L, posi >= 1, 2, "out of range");
-  luaL_argcheck(L, pose <= (lua_Integer)len, 3, "out of range");
+  luaL_argcheck(L, posi >= 1, 2, "out of bounds");
+  luaL_argcheck(L, pose <= (lua_Integer)len, 3, "out of bounds");
   if (posi > pose) return 0;  /* empty interval; return no values */
   if (pose - posi >= INT_MAX)  /* (lua_Integer -> int) overflow? */
     return luaL_error(L, "string slice too long");
@@ -187,7 +187,7 @@
   lua_Integer posi = (n >= 0) ? 1 : len + 1;
   posi = u_posrelat(luaL_optinteger(L, 3, posi), len);
   luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 3,
-                   "position out of range");
+                   "position out of bounds");
   if (n == 0) {
     /* find beginning of current byte sequence */
     while (posi > 0 && iscont(s + posi)) posi--;
diff --git a/testes/utf8.lua b/testes/utf8.lua
index 5954f6e..6010d1a 100644
--- a/testes/utf8.lua
+++ b/testes/utf8.lua
@@ -115,17 +115,17 @@
 end
 
 -- error in initial position for offset
-checkerror("position out of range", utf8.offset, "abc", 1, 5)
-checkerror("position out of range", utf8.offset, "abc", 1, -4)
-checkerror("position out of range", utf8.offset, "", 1, 2)
-checkerror("position out of range", utf8.offset, "", 1, -1)
+checkerror("position out of bounds", utf8.offset, "abc", 1, 5)
+checkerror("position out of bounds", utf8.offset, "abc", 1, -4)
+checkerror("position out of bounds", utf8.offset, "", 1, 2)
+checkerror("position out of bounds", utf8.offset, "", 1, -1)
 checkerror("continuation byte", utf8.offset, "𦧺", 1, 2)
 checkerror("continuation byte", utf8.offset, "𦧺", 1, 2)
 checkerror("continuation byte", utf8.offset, "\x80", 1)
 
 -- error in indices for len
-checkerror("out of string", utf8.len, "abc", 0, 2)
-checkerror("out of string", utf8.len, "abc", 1, 4)
+checkerror("out of bounds", utf8.len, "abc", 0, 2)
+checkerror("out of bounds", utf8.len, "abc", 1, 4)
 
 
 local s = "hello World"
@@ -140,11 +140,11 @@
   local t = {utf8.codepoint(s,1,#s - 1)}
   assert(#t == 3 and t[1] == 225 and t[2] == 233 and t[3] == 237)
   checkerror("invalid UTF%-8 code", utf8.codepoint, s, 1, #s)
-  checkerror("out of range", utf8.codepoint, s, #s + 1)
+  checkerror("out of bounds", utf8.codepoint, s, #s + 1)
   t = {utf8.codepoint(s, 4, 3)}
   assert(#t == 0)
-  checkerror("out of range", utf8.codepoint, s, -(#s + 1), 1)
-  checkerror("out of range", utf8.codepoint, s, 1, #s + 1)
+  checkerror("out of bounds", utf8.codepoint, s, -(#s + 1), 1)
+  checkerror("out of bounds", utf8.codepoint, s, 1, #s + 1)
   -- surrogates
   assert(utf8.codepoint("\u{D7FF}") == 0xD800 - 1)
   assert(utf8.codepoint("\u{E000}") == 0xDFFF + 1)