diff --git a/src/CHANGELOG b/src/CHANGELOG
index 66df0ea14..71fd98777 100755
--- a/src/CHANGELOG
+++ b/src/CHANGELOG
@@ -195,6 +195,8 @@ ECL 11.1.2
 
  - ECL will always build, by default, with support for Unicode strings.
 
+ - EXT:GETENV coerces its input argument to type BASE-STRING.
+
 ;;; Local Variables: ***
 ;;; mode:text ***
 ;;; fill-column:79 ***
diff --git a/src/c/main.d b/src/c/main.d
index acb0a4bdc..a87f34995 100644
--- a/src/c/main.d
+++ b/src/c/main.d
@@ -812,7 +812,8 @@ si_getenv(cl_object var)
 {
 	const char *value;
 
-	var = ecl_check_cl_type(@'ext::getenv', var, t_base_string);
+        /* Strings have to be null terminated base strings */
+	var = si_copy_to_simple_base_string(var);
 	value = getenv((char*)var->base_string.self);
 	@(return ((value == NULL)? Cnil : make_base_string_copy(value)))
 }