diff --git a/plugins/sudoers/mkdefaults b/plugins/sudoers/mkdefaults
index 77c7df936..89ddfb94e 100755
--- a/plugins/sudoers/mkdefaults
+++ b/plugins/sudoers/mkdefaults
@@ -25,7 +25,7 @@ if [ $# -eq 0 ]; then
     set -- def_data.in
 fi
 
-${AWK-awk} -f - -v outfile=$OUTFILE "$@" <<'EOF'
+${AWK-awk} -v outfile=$OUTFILE '
 BEGIN {
     tuple_values[0] = "never"
     tuple_keys["never"] = 0
@@ -49,8 +49,8 @@ BEGIN {
 }
 {
     sub(/#.*/, "", $0)
-    if (/^[[:blank:]]*$/) next
-    if (/^[[:alpha:]]/) {
+    if (/^[ \t]*$/) next
+    if (/^[a-zA-Z]/) {
 	# Store previous record and begin new one
 	if (var)
 	    records[count++] = sprintf("%s\n%s\n%s\n%s\n%s\n", var, type, desc, values, callback)
@@ -160,4 +160,4 @@ function print_record(rec, recnum) {
     }
     print "    }, {" > cfile
 }
-EOF
+' "$@"